Gallery specific issues

When debugging PowerPivot Gallery specific issues, you need to look at the various ways that the PowerPivot for SharePoint allows you to diagnose problems. Here are some tips and tricks for troubleshooting Gallery-specific issues:

A. Don’t forget the ULS

Like all things SharePoint, the ULS logs are your primary way of getting information on PowerPivot. Go their first for Gallery issues. In CTP3, there is a separate “Gemini.log” file that is generated in the ULS folder just for Gallery log entries. In RTM, all of this information is integrated into the ULS logs.

B. Generating thumbnails

As we said in the “Server-side issues” page, the first thing to do before you debug anything is to ensure that Excel Services is working. Go here for further information.

Once you have verified that Excel Services is working, the next step is to look at how thumbnails themselves are generate. Your most likely problem with thumbnails is that either a blank thumbnail is being generated or it contains a red “X”.

When a .xlsx is uploaded or published to Gallery, behind the scene, a process (GetSnapshot.exe) is created that ultimately generates the snapshot image (.png file) and saves in C:\Windows\temp. Here are some of the troubleshooting steps for this scenario:

• A simple test to see if a getsnapshot is being spawned is to:
  1. start task manager and click “show processes from all users”
  2. go to the document library and go to view “all documents” and just edit properties. This should cause GetSnapshot.exe to fire and you should see it under task manager and can see the account it is running under (CTP 2 it should be running under server farm account)
• Look in C:\Windows\Temp for the thumbnail (.png) and the log file .INFO; .INFO file should report success or failure messages
• Look in C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\LOGS for Gemini.log (this may later be added to SharePoint ULS logs)
• You can run GetSnapshot.exe manually and pass in parameters site, url, guid (note guid can be whatever). One caveat though is that the .info and .png file are created in the user’s local temp directory if they are logged in (as I was)…otherwise it will be saved in the c:\windows\temp. You cannot use this method to manually create/replace a thumbnail. This will only tell you if GetSnapshot failed (maybe b/c it took too long or something)

Another problem with the Gallery is that a blank thumbnail might be generated and it contains a “lock” icon. In this scenario, GetSnapshot.exe has determined that their might be a possible information disclosure and will not generate the image. This is likely caused by one of the following conditions:

1. The workbook might not contain any embedded PowerPivot data. If so, a thumbnail will not be generated.
2. The workbook might contain more than one data source. If so, a thumbnail will not be generated.
3. The single data source must point (via the “Server=” or “Data source=” property in the connection string) to either (a) the embedded PowerPivot database; or (b) to another workbook (.xlsx) that is contained in the same document library (i.e. the Gallery). If not, a thumbnail will not be generated.
4. If the file is a .rdl file, then the data source must be embedded in the report and it must use the PowerPivot OLEDB provider and point to a workbook (.xlsx) that is contained in the same document library (i.e. the Gallery). If not, a thumbnail will not be generated.

Gallery FAQ

How do you delete files in Report Gallery? You have to go to the document library Library Tools \ Library ribbon and change current view to All documents.