I have seen several cases where the background\parts of Excel workbooks are turning black:

Here is an example in the browser:

Here is an example from the PowerPivot Gallery:

From my experience the W3WP.exe is growing in size and this causes issues with performance.  Many times this is the result of a corrupt workbook.  I like to think of it this way; imagine opening a corrupt workbook on your machine in the Excel rich client.  If that workbook hangs, you will notice the Excel.exe process slowly growing in size when looking at Task Manager.  You will also experience performance issues on your machine.  The only way to close Excel is to kill (End Process) the Excel.exe in Task Manager.  If this happen on the server, the ExcelService.asmx will be trying to open this under the W3WP.exe.  You will see that the W3WP.exe is slowly growing in size until it affects the server performance.  Sometimes I am lucky and can find a corrupt workbook in the ULS logs, but this can be very difficult because performance issues can occur many hours after the workbook was opened.

05/20/2014 18:51:00.10   w3wp.exe (0x1A1C)            0x279C  Excel Services Application                Excel Calculation Services 2021       Information          Failed to load 'http://SharePoint.Contoso.com/sites/Documents/Services/Operations/Workbook.xlsx' with error: 'The workbook is corrupt.'. [Session: 1.V22.891OcC38Mp/PRDHw7Ze1tF90.5.en-US5.en-US73.+0360#0000-11-00-01T02:00:00:0000#+0000#0000-03-00-02T02:00:00:0000#-006036.b06179e8-2e64-440c-99a6-ca7f9f8d93161.N User: User@contoso.com]       3a9bffee-c087-48fb-b34e-8d968bdc6f24

If you find this corrupt workbook (note: there could be more than one) and remove/rebuild it, the issue will go away.  If you cannot locate this workbook (again, you may need to dig through massive ULS logs), you will need to Recycle the Excel Services Application Pool.

If you recycle the application pool daily (after hours), a growing W3WP.exe will be reset and you should be able to avoid see performance issues.

Here are instructions on how to recycle the application pool running Excel Services.

In IIS, you will need to expand “SharePoint Web Services” (make sure you are using “Content View”).  You will need to click on each GUID under “SharePoint Web Services” until you see the “ExcelService.asmx”, once you find this (special note, if you have multiple “Excel Services Service Applications”, there will be multiple GUIDs with the ExcelServices.asmx under it, you will need to either delete one of the “Excel Services Service Applications” or set both to Recycle), click on “Advanced Settings…”.  Here you will see the “Application Pool” once you find the GUID (in this case 9bf574c7cfc04e7e9a8595ec2e887fb8), you will know which Application Pool to Recycle.

Go to Application Pools> Right Click on 9bf574c7cfc04e7e9a8595ec2e887fb8> Advanced Settings…

You can set the time you want to Recycle under Recycling> Specific Times

You may receive the following error when running a scheduled data refresh on a PowerPivot workbook in SharePoint 2013 running PowerPivot for SharePoint:

Could not find the schedule for this work item

This error occurs when the workbook is checked out when the scheduled data refresh runs. Scheduled data refresh for workbooks that are checked out is not supported. The following article has further details:
 
http://msdn.microsoft.com/en-us/library/ee210651.aspx
 
It states that the workbook must be checked in at the time the refresh operation is finished. If the file is checked out to another user, the refreshed data will be thrown out.

You may see a "Call to Excel Services failed" error when trying to perform a scheduled data refresh using PowerPivot for SharePoint on a workbook in SharePoint 2013 that has a Power Query connection to a data source. At this time, Power Query is not supported by SharePoint 2013 on-premise. It is only supported by Power BI for Office 365 (SharePoint Online).

http://blogs.msdn.com/b/powerbi/archive/2014/05/02/scheduled-data-refresh-for-power-query.aspx

As a workaround, you can connect to the data source without using Power Query by creating a data connection using PowerPivot. To determine whether or not the workbook currently has a Power Query data connection, look at the connection string in Excel by going to Data > Connections > Properties >  Definition. If the Provider is Microsoft.Mashup.OleDb.1, this indicates that the data connection was made using Power Query.

Issue:

Users server has SQL Server 2014 version of PowerPivot

User creates a PowerPivot workbook with Excel, and saves it to SharePoint.

User creates a .bism file that points to the PowerPivot workbook and saves the .bism file to SharePoint.

User creates second workbook that uses the .bism file to point to the first PowerPivot workbook as a data source.

User views the workbook with Excel Services and tries to slice the data.

User gets error "An error occurred during an attempt to establish a connection to the external data source.  The following connections failed to refresh."

There is a software defect that prevents .bism files from working for this use case.

Workaround:

Instead of creating a .bism file, create a .odc file and use that.

How to create .odc file and data connection library

http://msdn.microsoft.com/en-us/library/office/ms772101(v=office.14).aspx

Issue

As we all know :) with SharePoint 2013, manual data refresh in the browser (Data > Refresh All Connections) for PowerPivot workbooks will refresh data all the way back from the original PowerPivot data source, which is specified in the PowerPivot workbook's PowerPivot connection. This functionality is different with SharePoint 2010, where manual data refresh in the browser (Data > Refresh All Connections) will refresh data only from the cube (in its current state) that exists for that PowerPivot workbook in the PowerPivot instance of Analysis Services.

The Issue: With SharePoint 2013, we have found that a PowerPivot workbook with a PowerPivot connection to a SharePoint list cannot be refreshed manually in the browser (Data > Refresh All Connections) using Windows authentication in SharePoint 2013.

Many have tried to get this refresh functionality working using a number of different Service Principle Name and constrained delegation settings and configurations, and so far efforts have been unsuccessful with getting delegation to work.

Workaround

In this scenario, the workaround is to use a Secure Store ID for the workbook list connection, instead of using Windows authentication.

Of course, the SSS ID (mine was PowerPivotUnattendedAccount) will need to have credentials set for it that have permissions to the SharePoint list that is being refreshed from.

When you first install PowerPivot for SharePoint, there are some configuration tasks that need to be completed to get basic functionality working for the PowerPivot Management Dashboard, as well as to get the groundwork laid out for data refresh and slicing inside of workbooks.

While not difficult to do, these steps are often missed and we see quite a few support cases opened up for these simple configuration issues.

These items are not in any particular order, but all of them are relevant to every installation of PowerPivot for SharePoint 2010 and 2013 (Unless otherwise noted). All of these tasks should be completed after the successful installation of the PowerPivot Analysis Services SQL instance as well as the running of the PowerPivot Configuration Tool on at least one server in the farm successfully.

For this example, I will use screenshots from one of my isolated test farms, so please do not take the names of servers or service accounts literally. They will be different for every scenario depending on your configuration.

Also, I will not be covering Kerberos or any data refresh configuration as part of this article. Nor will I be covering any troubleshooting. This will only cover getting the PowerPivot Management Dashboard into a working state after a fresh install.

• Ensure that the spPowerPivot.msi has been installed on all servers in the farm.Note that this will provision the PowerPivot configuration tool on all servers, but you do not have to run it. The main reason here is to install the ADOMD.NET drivers that are relevant to your install. You can also download the ADOMD.NET drivers from the SQL Server feature pack that is relevant to the version of SQL you are using for your PowerPivot AS instance.
  • Note that the version of the spPowerPivot.msi and\or ADOMD.NET drivers you install will depend on your version of PowerPivot AS. For instance, if you are using SQL 2014, the SQL 2012 SP1 version of the msi will not install the proper drivers.
    • SQL 2014 Feature Pack: http://www.microsoft.com/en-us/download/details.aspx?id=42295
    • SQL 2014 PowerPivot Add-in for Sharepoint: http://www.microsoft.com/en-us/download/details.aspx?id=42300
    • SQL 2012 SP1 Feature Pack: http://www.microsoft.com/en-us/download/details.aspx?id=35580
    • SQL 2012 SP1 PowerPivot Add-in for SharePoint: http://www.microsoft.com/en-us/download/details.aspx?id=35577
    • SQL 2012 SP2 PowerPivot Add-in for SharePoint: http://www.microsoft.com/en-us/download/details.aspx?id=43342
    • SQL 2008 R2 SP1 Feature Pack: http://www.microsoft.com/en-us/download/details.aspx?id=26728
    • Note that SQL 2008 R2 does not have a PowerPivot add-in as it is required to set up the PowerPivot AS instance on one of the SharePoint servers. The "add-in" is implemented into the farm as part of the installation of the instance.

• Define your PowerPivot instance (SharePoint 2013 ONLY)
  • We need to tell SharePoint which PowerPivot AS instance we are using to host data models. In Central Administration, navigate to your Excel Services service application and click on "Data Model Settings".
    • Add your PowerPivot instance here in the "servername\PowerPivot" format:
      
      In this example, my PowerPivot instance is hosted on a server named "Reporting", therefore my PowerPivot AS instance is denoted as such: "servername\PowerPivot"

• Define your unattended account for PowerPivot.
  • During the running of the configuration tool, it creates an unattended data refresh account inside of the Secure Store service. Within the scope of PowerPivot, this account is used to populate the information inside of the PowerPivot Management Dashboard. As this ID is already configured, all we need to do is define a service account to be stored in the ID. This service account must have at least "db_reader" permissions on the PowerPivot Service Application database. This database is located with the rest of your service application databases on whatever instance stores your SharePoint databases. Unless you explicitly changed its name during configuration, it can usually be identified by the service application name followed by a GUID just like in the screenshot below:
    
    

• • • To define this account, navigate to your Secure Store Service application in Central Administration.
      • Find the Secure Store ID labeled "PowerPivotUnattendedAccount"
      • Hover your mouse over the ID and click the dropdown menu.
      • Click "Set Credentials"
      • Enter a farm account for a Credential Owner if there isn't one present.
      • Enter the desired data access account in the "Windows User Name" field in a "domain\username" format.
      • Enter and confirm the password.
      • Click "OK"
    • Navigate to your PowerPivot Service application and click "Configure service application settings"
  • • Find the "PowerPivot Unattended Data Refresh Account" field, and ensure that the "PowerPivotUnattendedAccount" is listed. If it isn't, enter it here, and then click "OK"
      
      

• If you are using different service accounts for all of your services, you may need to run the following PowerShell commands to give your Excel Services account access to Central Admin. This will allow the service to render workbooks in the browser.
  • Run the following from an administrator enabled SharePoint 2013 Management Shell:
    • $w = Get-SPWebApplication –Identity <URL of the Central Administration>
    • $w.GrantAccessToProcessIdentity("<insert Excel Services service account here>")
      
      
• Make the Excel Services and PowerPivot service accounts Administrators on the PowerPivot Analysis Services instance. This is required for the appropriate services to create and manage data models on the instance.
  • Open up SQL management Studio and connect to your PowerPivot AS instance.
  • Right click on the root node and select "Properties"
    
    
  • Click "Security"
  • In this section, ensure that your accounts that run the PowerPivot Service application and Excel Services are listed. If they are not, add them.
    
    Note that my screenshot has a few more accounts added…..ignore them.
    
    
• After the accounts are added, click "OK" and close out of SQL management Studio.

After all of this is done, you can test to see if the dashboard will retrieve data when it is available by force running the PowerPivot Management Dashboard Processing Timer Job.

• Navigate to your PowerPivot Service Application and click "Review Timer Job Definitions".
• Click "PowerPivot Management Dashboard Processing Timer Job".
• Click "Run Now", then "Job History" once the page loads.
• Refresh this page until you see the timer job near or at the top of the list. If the status is succeeded, you can go back to the Management Dashboard, though it is unlikely to populate any usable data as no workbook activity has been recorded yet.
  • If this timer job fails, you will need to troubleshoot the error. Most of the steps I went through above cover most of the troubleshooting needed to resolve this. 9 times out of 10, the unattended account either isn't properly set or does not have the correct permissions on the PowerPivot Service Application database. You may have to dig into the ULS logs to uncover the error if it is not obvious.
    
    

Barring any other unforeseen issues, after a few days of using PowerPivot in your environment, you should start seeing data populated inside of the dashboard. Note that this data is not updated in real time. It utilizes the SharePoint Web Analytics to populate data, so at a minimum you will see updates every 24-48 hours.

Interested in other post configuration tasks? Check out our blog for more!

http://blogs.technet.com/b/excel_services__powerpivot_for_sharepoint_support_blog/

We have seen several cases where customers can view an Excel Workbook in the browser, but not in the Excel Web Access Web Part.  They are seeing the below error in the Excel Web Access Web Part:

“Excel Services

We don’t know what happened, but

something went wrong. 

Could you please try that again?”

When reviewing the ULS logs, we are seeing:

11/24/2014 11:37:37.26 w3wp.exe (0x2864) 0x0BBC SharePoint Foundation Database d0d6 High System.Data.SqlClient.SqlException (0x80131904): The EXECUTE permission was denied on the object 'rbs_fn_get_blob_reference', database 'SharePoint_Content_80', schema 'mssqlrbs'.     at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)     at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)     at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady)     at System.Data.SqlClient.SqlDataReader.TryHasMoreRows(Boolean& moreRows)     at System.Data.SqlClient.SqlDataReader.TryReadInternal(Boolean setTimeout, Boolean& more)     at System.Data.SqlClient.SqlDataReader.Read()     at Microsoft.SharePoint.SPSqlClient.ExecuteQueryInternal(Boolean retryfordeadlock)     at Microsoft.SharePoint.SPSqlClient.ExecuteQuery(Boolean retryfordeadlock)  ClientConnectionId:932b5260-fed3-44df-9e6a-72292182dfd9 c057cf9c-9345-605f-7c08-0f50fcd1dfd4

This has to do with permissions and to resolve this, grant the following permissions to the Application Pool account on the content database:

db_rbs_admin

db_rbs_filestream_maintaner_1

db_rbs_filestream_reader_1

db_rbs_filestream_writer_1

db_rbs_maintainer

db_rbs_reader

db_rbs_writer

Issue:

The PowerPivot management dashboard does not show all usage data like it is suppose to and you see that the PowerPivot Management Dashboard Processing Timer Job fails.

You may see errors like:

"Call to Excel Services returned an error"

“Cannot query internal supporting structures for column 'Date'[Rolling52Weeks] because they depend on a column, relationship, or measure that is not processed. Please refresh or recalculate the model”

Verify Issue:

The error information can be generic and not very useful for this issue.  You can verify this specific issue by starting SQL Server Management Studio and pointing it to your PowerPivot Service Application database, it is likely on the same SQL Server as you SharePoint 2013 content databases.  The database will likely be named something like this "DefaultPowerPivotServiceApplicationDB-57bc03ae-bd41-4102-ab6f-f03201e3b583"

Expand the database in the tree and expand the Views folder.

Right click on Usage.vDate and pick "Select top 1000 rows"

Scroll all the way to the right in the results grid and look at the values for the "Today" column.

If the "Today" column has NULL in it this is our problem (the column should have a valid date in it)

Workaround:

Open a new query window to the PowerPivot Service application database (same as referenced in the above steps)

Run this command:

EXECUTE sp_refreshviewN'Usage.vDate';

More Info:

This issue was caused because the table the view references has been modified and the view was put into an invalid state.

I am working with the product group to have SQL updates refresh these views automatically.

Many customers come to us with questions surrounding the use of BISM files.  Primarily why should they use them and how to configure them.  In the following I will attempt to answer both questions.

Why:

When you upload a PowerPivot workbook to SharePoint, SharePoint is intelligent enough to create a Data Model under the Analysis Services PowerPivot Instance (If you have an Analysis Services Server in PowerPivot Mode and listed under the Excel Services > Data Model Settings).  You now have a Data Model using Microsoft's In Memory X-Velocity technology and all you had to do was upload a PowerPivot workbook to SharePoint!  This workbook could hypothetically be up to 2GB in size (SharePoint's file limitation is 2GB) and lets also say you want to create 10 unique reports off that same data.  You could re-create 10 identical workbooks in the Excel Rich Client, upload them to SharePoint ,and these workbooks would all have their own Data Models occupying system memory OR you could point these 10 thin (or shim) Excel workbooks to that one already existing Data Model.  This is great because you don't have to load 10 individual 2GB Data Models under the PowerPivot Instance. 

These BISM files are essentially connection files (like an .odc) to Data Source.  If you do not want to grant users certain permission to an actual database, but you want them to be able to build reports in Excel off of data from that database, you can achieve this via BISM files.  Users can access this data (Data Model), build reports, and these workbooks will show fresh data daily (as long as you configure a Scheduled Data Refresh to the source PowerPivot workbook).

Lastly, if you click on the BISM file (or choose Create Power View Report), it will load a PowerView Report.

How:

First you need to add the BI Semantic Connection Content Type.  To do this, you will need to browse to Library Settings

Click on Advanced Settings

Choose Yes under Allow management of content types?

Click Add from existing site content types

Choose BI Semantic Model Connection and click Add >

Browse to the document library, choose the File tab > New Document> BI Semantic Model Connection

This will open a New BI Semantic Model Connection, name the item and then add the URL of the PowerPivot workbook in SharePoint.  In this example, the PowerPivot workbook will be stored in the same location as the BISM file, we merely right clicked on the workbook and chose Properties (http://sp/Shared%20Documents/PowerPivotWorkbook.xlsx):

You now have a BISM file that points to the PowerPivot workbook in SharePoint

You can choose to open this in PowerView via Create PowerView Report

As you can see, this opens a PowerView Report

You can also use this BISM file in Excel, but first you will want to make note of the BISM URL.  Right click on the BISM file and choose Properties (http://sp/Shared%20Documents/BISM%20File.bism):

Launch the Excel Rich Client > click the Data tab > From Other Sources> From Analysis Services

Paste the BISM URL (http://sp/Shared%20Documents/BISM%20File.bism) next to Server Name: and click Next >

As you can see, this will find the Data Model located under the Analysis Services PowerPivot Instance

Data Model under the Analysis Services PowerPivot Instance via SQL Management Studio

You can then modify the File Name: and Friendly Name: (I chose "BISM Connection") > Finish

Choose PivotTable Report > OK

You can then build your PivotTable and insert Slicers via PIVOTTABLE TOOLS (make sure you have the PivotTable select so the Contextual Tool Tab is present) > ANALYZE > Insert Slicer

 Save and Publish this workbook to SharePoint

You can now open this workbook in Excel Services and interact with the Data Model.

IMPORTANT:

At the moment, there is a bug in the product and you will not be able to interact with the Data Model in Excel Services when pointing to a BISM file built off a PowerPivot workbook stored in SharePoint 2013.  You will get the error:

"External Data Refresh Failed

An error occurred during an attempt to establish a connection to the external data source.  The following connections failed to refresh:

BISM Connection"

If you run a SQL Profile Trace against this Analysis Services PowerPivot Instance while reproducing this error, you will see the Error"You do not have permission to perform the requested operation."

This was fixed in SQL 2014 CU5:

Cumulative update package 5 for SQL Server 2014
http://support.microsoft.com/kb/3011055

KB Article:

Excel Services workbook fails to refresh using a .bism file
http://support.microsoft.com/kb/3016518

We have worked several cases where BISM icons are no longer present in a SharePoint Library.  In the below screenshot you can see the icon is a blank square.

We have found that the mapping is no longer present in the DOCICON located in one of the two directories (dependant on the version you are using):

C:\Program Files\Common Files\microsoft shared\Web Server Extensions\14\TEMPLATE\XML
C:\Program Files\Common Files\microsoft shared\Web Server Extensions\15\TEMPLATE\XML

The missing mapping is: <Mapping Key="bism" Value="PowerPivot\icbism.png" />

This points to the icbism.png

You will want to add this to the DOCICON and Save.

Note: You may need to Stop and Start IIS, because the file may have a lock on it.

As you can now see the BISM Icon is now present!

Issue

In some scenarios, an Excel Web Access web part won’t display an Excel workbook that will display correctly with Excel Services (xlviewer). Instead of seeing the published workbook contents in the web part, there is just a placeholder icon where the workbook should be displayed, and there are no errors in the web part or on the page.

In this scenario, if you look at the Internet Explorer Developer Tools (IE > Tools > Developer Tools) while you attempt to display an Excel workbook in an Excel Web Access web part, you may see errors like this one “TypeError: o.getName is not a function”.

We have seen this issue with at least these versions of SharePoint 2013: 

• 15.0.4420.1017
• 15.0.4569.1000

Cause

This can be caused by an issue with compatibility between the .NET AJAX Control Toolkit and the Excel Web Access web part.

Workaround

Do not use the .NET AJAX Control Toolkit to implement Ajax functionality for a site using Excel Web Access web parts.

Issue:

You are trying to create a PowerPivot model in an Excel workbook by fetching data from a .atomsvc file, or you want to data refresh a PowerPivot workbook that has a .atomsvc file in it.

You will get errors when doing the above activities.

"The payload kind 'BinaryValue' of the given data feed is not supported.
----------------------------
Failed to connect to the server. Reason: The payload kind 'BinaryValue' of the given data feed is not supported."

Workaround:

A .atomsvc file is just a file that contains a pointer to the real data source, like a SSRS report or a SharePoint list.  Instead of creating the PowerPivot data model with the .atomsvc file as the source, simply use a URL to the actual data source.

For a SSRS report it would look something like this:

http://sp2013ocsi/_vti_bin/ReportServer?http://sp2013ocsi/Shared Documents/EMEA1.rdl&rs:Command=Render&rs:Format=ATOM&rc:ItemPath=Tablix1

The ReportServer API is documented at:

http://msdn.microsoft.com/en-us/library/ms152835.aspx

Or for a SharePoint list:

http://sp2013ocsi/_vti_bin/ListData.svc/HTMLList

Issue

This solution was tested with PowerPivot 2012 for SharePoint 2013.

If you need to get PowerPivot scheduled data refresh to work for a PowerPivot workbook that has a PowerPivot add-in connection in it that uses embedded SQL credentials for refreshing from the data source, like below, then there are a few important additional settings that need to be set in order for it to work.

Solution

In the workbook connection (Data > Connections, the “Save Password” option here also needs to also be selected.

Also the Excel Services Authentication should be set to "Use the authenticated user's account".

Finally, when setting up the refresh schedule for the PowerPivot workbook in the PowerPivot gallery ("Configure Schedule"), chose these options at the bottom:

• "Use the Default Schedule"
• "Use the credentials contained in the workbook"

If the settings above are not used, then what will happen is:

1. When you open the workbook in Excel, and then open the PowerPivot add-in, and then attempt to refresh the PowerPivot add-in connection, you will get prompted there for the SQL password (this is what causes the PowerPivot scheduled refresh to fail in the background).
2. The PowerPivot scheduled refresh will fail with an error in the refresh history: "Call to Excel Services returned an error".
3. You will see errors in the ULS logs like these:

01/06/2015 12:49:52.80   w3wp.exe (0x088C)            0x1764  Excel Services Application External Data        ajesn       Medium                ASPPHOST::ShowEngineError: Out of line object 'DataSource', referring to ID(s) '78c26543-e488-4bf2-9e41-9d83ea35b126', has been specified but has not been used.  OLE DB or ODBC error: Login failed for user 'SQLuserACCT'.; 28000.                 

01/06/2015 12:49:52.80   w3wp.exe (0x088C)            0x1764  Excel Services Application External Data        ajeso       Information                Failed to create an external connection or execute a query. Provider message: Out of line object 'DataSource', referring to ID(s) '78c26543-e488-4bf2-9e41-9d83ea35b126', has been specified but has not been used.  OLE DB or ODBC error: Login failed for user 'SQLuserACCT'.; 28000.  , ConnectionName: ThisWorkbookDataModel, Workbook: ExcelWorkbookName.xlsx.          

01/06/2015 12:49:52.99   w3wp.exe (0x088C)            0x286C  Unknown               AS SPClient            513         High        Hit ECS exception name: 'ExternalDataRefreshFailed'; message:'An error occurred while working on the Data Model in the workbook. Please try again.    We were unable to refresh one or more data connections in this workbook.  The following connections failed to refresh:    WorkbookConnectionName  '       

01/06/2015 12:49:53.27   w3wp.exe (0x088C)            0x286C  PowerPivot Service             Data Refresh         99           High                EXCEPTION: System.InvalidOperationException: Call to Excel Services returned an error. ---> Microsoft.AnalysisServices.SPClient.Interfaces.ExcelServicesException: ECS failed with non-zero return status. First error is name='ExternalDataRefreshFailed'; message='An error occurred while working on the Data Model in the workbook. Please try again.    We were unable to refresh one or more data connections in this workbook.  The following connections failed to refresh:    WorkbookConnectionName

You may see the following error when using Excel to make a data connection to a PowerPivot workbook, or during a scheduled refresh of a PowerPivot workbook that uses another PowerPivot workbook as a data source on SharePoint 2010:

XML parsing failed at line 1, column1: Incorrect document syntax

This could be caused by a Service Pack update to SharePoint 2010. To resolve the issue, reinstall the SQL 2012 version of the MSOLAP data provider (MSOLAP.5) by following the instructions in this article:

http://msdn.microsoft.com/en-us/library/ee210608.aspx

Issue

This has been reproduced with Excel 2013 and SharePoint 2007 SP3.

There is an issue with using Excel Services for SharePoint 2007 to open Excel workbooks that were created with Excel 2013.

If you attempt to open an Excel workbook in the browser that was created with Excel 2013 using Excel Services for SharePoint 2007, you will get an error like this saying that the workbook may be in an unsupported file format, or it may be corrupt”:

Cause

UPDATE: The issue is a side-effect of changes/enhancements that were made to the XML for .xlsx files for Excel 2013, which are not present in Excel 2007 or Excel 2010 files.

Workaround

This issue does not exist for workbooks that were created with Excel 2007 or with Excel 2010.

Excel Services for SharePoint 2013 will open workbooks that were created with Excel 2007, Excel 2010, or Excel 2013.

I have worked with many customers who have not re-run the PowerPivot Configuration Tool after upgrading the Analysis Service POWERPIVOT Instance.  You need to do this.  This is how and why.

Click on the "PowerPivot for SharePoint 2013 Configuration"

Choose "Configure or Repair PowerPivot for SharePoint" > OK

This will analyze your system and will notice if you have upgraded the Analysis Services Server.  If it notices an upgrade, it will let you know.

Here is an example.  Let's say you run across an issue with the Scheduled Data Refresh and this blog fixed the issue.

PowerPivot for SharePoint 2010 & SQL 2012 - Refresh in browser fails due to multiple "Process" Data Models in Analysis Services.
http://blogs.technet.com/b/excel_services__powerpivot_for_sharepoint_support_blog/archive/2013/05/23/powerpivot-for-sharepoint-2010-amp-sql-2012-refresh-in-browser-fails-sue-to-multiple-quot-process-quot-data-models-in-analysis-services.aspx

To fix this issue, you need to apply a Cumulative Update to Analysis Services:

Cumulative update package 4 for SQL Server 2012 SP1
http://support.microsoft.com/kb/2833645/en-us 

Once you apply this CU, the Analysis Services build will be 11.0.3368.0.  But the PowerPivot Configuration Tool build will be that of (most likely) SP1 (11.0.3000.0).  You need to re-run the tool so they are standardized.  You might ask, "Why do I have to do this?"  Well, think about it, if you do not have deploy the PowerPivot Configuration Tool in the first place, you won't have the PowerPivot Management Dashboard or Scheduled Data Refresh functionality.  So if a fix is to one of those areas, you need to re-run the PowerPivot Configuration Tool.  When you run it, it will detect the changes to Analysis Services; and say"Newer versions of the PowerPivot solution files have been detected.  Please select the upgrade option to upgrade your farm."

 You will then need to "Upgrade Features, Services, Applications and Solutions" > OK

IMPORTANT NOTE:

Once you upgrade SQL Server to SP2, you will want to install this version of the PowerPivot Configuration Tool:

Microsoft® SQL Server® 2012 SP2 PowerPivot® for Microsoft SharePoint 2013®
http://www.microsoft.com/en-us/download/details.aspx?id=43342

Jason discusses running the Tool here to fix an issue, but you need to run this tool every time you apply and upgrade to the Analysis Services POWERPIVOT Instance.

I have had several customers experience the PowerPivot "scheduled data refresh" running over and over when setting the Schedule Details to Monthly and choosing a Day.

Refresh Settings:

As you can see below, the refresh runs over and over; it's stuck in a loop.  In this case every 5 seconds.  If the Data Model was larger and required more data to refresh, the duration would be longer.

We were able to fix this in the below CU:

Cumulative Update 4 for SQL Server 2012 SP2

http://support.microsoft.com/kb/3007556

FIX: Continuous refreshes occur after you configure scheduled data refresh in PowerPivot for SharePoint 2013

http://support.microsoft.com/kb/3023620

Important Note:

Run the "PowerPivot Configuration Tool" after Upgrading the Analysis Services POWERPIVOT Instance.
http://blogs.technet.com/b/excel_services__powerpivot_for_sharepoint_support_blog/archive/2015/03/12/run-the-quot-powerpivot-configuration-tool-quot-after-upgrading-analysis-services-powerpivot-instance.aspx 

You may encounter a data refresh for a PowerPivot workbook in SharePoint error due to issues with Perfomance Counters on the PowerPivot Analysis Services server. You may see the following error in the ULS log:

EXCEPTION: System.ComponentModel.Win32Exception (0x80004005): Access is denied at System.Diagnostics.PerformanceMonitor.Init()

This may indicate that the PowerPivot System Service does not have permissions to the Performance Counters on the server running PowerPivot Analysis Services. To fix the error, add the account running the PowerPivot System Service application pool to the Perfomance Log Users and Performance Monitor Users groups by going to Computer Management >  Local Users and Groups > Groups

 A different error you may see in the ULS log is the following:

The '\MSOLAP$POWERPIVOT:Memory\Memory Limit High KB' performance counter could not be found.

This means that the Performance Counters for PowerPivot have not been loaded. Check the Registry by running regedit.exe and look for the following key:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSOLAP$POWERPIVOT\Performance\Disable Performance Counters

If it is set to 1, the Performance Counters for PowerPivot Analysis Services is disabled. Set the value to 2 to enable the counters.

If that does not fix the error, you may have to run the following commands in a command prompt to recreate the counters:

unlodctr msolap$pwerpivot

lodctr perf-MSOLAP$POWERPIVOTmsmdctr.ini

Issue

Consider this scenario:

You have a SharePoint 2013 environment with the PowerPivot 2012 add-in for SharePoint installed. You have non-PowerPivot workbooks in your PowerPivot gallery, and you have successfully set up scheduled data refreshes for those non-PowerPivot workbooks. When you upload the non-PowerPivot workbooks to the PowerPivot gallery, thumbnails for those workbooks are generated successfully. Then when you run a scheduled data refresh for a non-PowerPivot workbook, the thumbnail for that workbook may give you a red x.

An example of a non-PowerPivot workbook is a workbook that was created with a regular non-PowerPivot connection in it to a SQL or OLAP data source (i.e. the PowerPivot add-in was not involved in the creation of the workbook, and the workbook has no embedded PowerPivot data in it).

Cause

For all versions of PowerPivot for SharePoint, scheduled data refresh is not supported for non-PowerPivot workbooks.

In the scenario described above, scheduled data refresh for non-PowerPivot workbooks may work, but this functionality was not tested or intended to work.

This unsupported refresh functionality may have unintended side-effects, such as the thumbnails for the workbooks being broken in the PowerPivot gallery when the scheduled refresh occurs (and getting a red x instead of properly-generated thumbnail images). PowerPivot scheduled data refresh was only intended to be used with (and is only supported for) PowerPivot workbooks (i.e. workbooks that were created using the PowerPivot add-in in Excel). It is not generally recommended to use unsupported or unintended functionality in a production environment.

Workaround

One possible workaround for this unsupported scenario is to open the workbook in the Excel client, refresh the workbook, and then save the workbook back to the PowerPivot gallery. Another workaround is to make a small change to the title (not the name) of the workbook. These workarounds may or may not work, and they may or may not be appropriate for your particular needs, and are unsupported, but they could be useful in some situations, such as for when non-PowerPivot workbooks are set to refresh less frequently (ex. one time per month).

Over the last few months, we have seen a few more instances of people using data sources that require a DSN connection to retrieve data for PowerPivot and Excel workbooks. Normally, if you are just using these data connections inside the client, you just refer to the DSN as a data source and all is well. This changes while attempting to utilize this data source from within SharePoint as Excel Services and PowerPivot do not understand DSNs and fail to connect.

To this end, this blog will cover a basic scenario where a DSN is required to connect to a data source. This may not cover EVERY scenario because every data source is different, but it should be a solid guide on how to get started. For my example I will use Amazon RedShift as I recently worked a case with this data source.

The Setup:

With my Data Source and sample data created and configured, I begin by installing the appropriate x64 drivers on my servers. In some cases, you may have a 32-bit client. This is fine, but note that Excel Services and PowerPivot will only use x64 drivers to connect. You will need to contact your data source vendor to obtain the appropriate drivers to install. This is not something we can generally provide as we would be doing searches online just like you.

I am doing this example in SharePoint 2013, but this process will hold true for SharePoint 2010 as well. Also, the workbook I create will be within the scope of Excel rather than PowerPivot because PowerPivot does not support connections to RedShift. You will find that for the "Odd data source type" it will be trial an error whether or not your connections will work properly with PowerPivot. Some may work only in Excel, and some may work for both.

After the drivers are installed, I configure my DSNs. Here are a few things to remember:

- Even if you use the 32-bit driver on your client, you MUST use the 64-bit driver on the server.

- The DSN nameMUST be the same on the server and the client. (regardless of the driver version)

- Use a System DSN and not a User DSN.

- Create the DSN on ALL servers hosting Excel Services and PowerPivot Analysis Services. (In SharePoint 2010, these will be SharePoint servers, in SharePoint 2013, the PowerPivot Analysis Services servers may be outside of the farm).

When you finish entering the information for the DSN on the server, make sure you test the connection. If it is unable to connect with the DSN, Excel\PowerPivot will not be able to connect and you may get errors that don’t really mean anything in the logs:

Once the DSNs have been created and confirmed working, we can start configuring SharePoint.

Navigate to the following in Central Administration:

"Central Administration > Application Management > Manage Service Applications > Excel Services Application > Trusted Data Providers"

Add the MSDASQL.1 provider to this list (this is the provider we will use to connect to the DSN).

We then need to recycle Excel Services:

1. Stop Excel Calculation Services on all servers in the farm.
2. IIS reset those servers.
3. Start Excel Calculation Services on those servers again.

You will also need to create a Secure Store ID containing the credentials you wish to connect to the data source with.

Lastly, we will create our workbook.

Click on "Data > From Other Sources > From Data Connection Wizard > Other/Advanced"

Click "Next"

Choose "Microsoft OLE DB Provider for ODBC Drivers"

Click "Next"

Enter the name of your DSN in the "Use data source name" field.

Test the connection to validate it is working, and then click "OK"

From here, build your workbook as you normally would.

Make sure to modify the data connection to use the "Secure Store" in Excel Services.

Navigate to "Data > Connections > Properties > Definition > Authentication Settings

Choose "Use a stored account" and enter the secure store ID you created for this data source.

Save the workbook and upload it to a SharePoint library.

Open the workbook in the browser and test the refresh.

Enjoy!

For more blogs by our team and/or more troubleshooting help, check out the main blog!

http://blogs.technet.com/b/excel_services__powerpivot_for_sharepoint_support_blog/