Work Item Synchronization issue with Update 2

After installing the Team Foundation Server 2012 Update 2 it can happen that the Work Item Tracking Synchronization Service suddenly stops working, so that you can’t see updated areas and iterations neither in Visual Studio, Web Access, Excel, etc.

These are the symptoms…

To help us troubleshooting this nasty – but known – bug, the _oi Activity Logs are very helpful…

  We see that from a certain point, a number of Work Item Tracking Integration Synchronization jobs are failing…

…and the Job History Details show a System.NullReferenceException. Here is the problem!

The Team Foundation Server 2012 Update 3 contains a fix for this, as detailed into the changelog (see the Work Item Tracking paragraph into the Team Foundation Server fixes).