Yesterday after I uninstalled my VS2012 (since I have VS2013 installed) , I found that I could not edit document properties with this message:
The server was unable to save the form at this time. Please try again.
I then looked at the SP log file:
Error when processing types in server stub DLL Microsoft.SharePoint.Client.ServerRuntime, Version=126.96.36.199, Culture=neutral, PublicKeyToken=71e9bce111e9429c
System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.Data.Edm, Version=188.8.131.52, Culture=neutral, PublicKeyToken=31bf3856ad364e35
System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.Data.OData, Version=184.108.40.206, Culture=neutral, PublicKeyToken=31bf3856ad364e35
seems like the WCF Odata Services got uninstalled as well.
The solution is to reinstall it:
and then restart your server.