We were in a situation were the “Workbook Activity – Chart” of the PowerPivot Management Dashboard was showing a red X. Our authentication provider is Kerberos so we applied the according SPN to our accounts. We also modified the web.config file of PowerPivot web service to support Kerberos delegation. We were also aware that ADOMD.NET in required on the server running the Central Administration site if you don’t want to have that specific red X. Our farm is under SharePoint 2013 and when you install the spPowerPivot.msi package from SQL Server 2012 it is installing ADOMD.NET package. We decided to install it manually to make sure it’s not an issue with the install but the error was still present. We went through the ULS logs and nothing was showing us that an issue is happening except this entry:
“System.Runtime.InteropServices.COMException: The file you are attempting to save or retrieve has been blocked from this Web site by the server administrators”
Again, when looking at the logs, we validated that the Central Administration site was configured in the “Trusted File Location” of the Excel Service. We decided then to look at the Event Viewer on the server and were hoping something interesting could be present. We were seeing an error but were thinking it is not related since our farm was not still live and our web applications were in NTLM to not break our actual production under SharePoint 2010.
We decided to refresh the page and noticed that the refresh triggered the error again. We then look directly in IIS for the authentication providers of the Windows authentication and found out that only NTLM was present. We added Negotiate and the issue was fixed. The issue was coming from a configuration that didn’t get applied when we changed the authentication provider of the Central Administration site. It was correctly applied in another environment so we probably faced a bug when we did our change. At least, everything is now running well.
We found out a small issue with PowerPivot 2012 and SharePoint 2013 this week.
You may be aware that the PowerPivot for SharePoint is able to create snapshots/thumbnail previews of your document which is then used to display a nice little image in the carrousel view.
This fancy little feature is generated under the hood by an executable located in the bin folder of the SharePoint installation folder (C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\15\bin).
While it works well under common context, it will fail in a particular scenario. I won’t give you all the different ways to troubleshoot this as Internet already as a ton of article around it but here’s one that is very useful :
Our scenario is as follow :
- The server hosting SharePoint and Powerpivot is running Windows 2012
- Windows Server 2012 is configured using MSI (Minimal Server Interface)
In this particular case, the “GallerySnapshot.exe” will crashes when processing the document.
If you look in the “info” file generated, you quickly find out that there is nothing relevant to help you. Here’s the content of the log file :
“<SnapshotCaptureLog serverUrl=”http://<webapp name>” workbookUrl=”http://<site url>/SharePoint/PpowerPivot/Book1.xlsx” fileNameBase=”thumbnail” snapshotCount=”26″ timeout=”600″ />”. That’s it ! Nothing else.
In the “GallerySnapshot.exe has stopped working” error window details, we can see a small hint of what’s going on : “Problem Signature 04: System.Windows.Forms”.
I performed the same exercise on a different server with the same result. I then intalled the windows feature Server Graphical Shell (Install-WindowsFeature Server-Gui-Shell) and restarted the server.
Once rebooted, running the GallerySnapshot.exe again with the same arguments went successfully.
To sum-up, if you require the file preview in a PowerPivot Gallery, you will necessarily have to configure your servers with at least the Graphical User Interface. Let’s hope Microsoft will remove this pre-requisite in a future cumulative update or service pack but until then, forget Windows Server 2012 MSI !
Sad, sad, sad.