After upgrade the project references are all referred to the older version even though the installed version is the latest and the tests are failing with an error loading referenced assembly . When the project references are manually updated , the problem is solved, however this creates huge inconvenience for customers with multiple projects.

Exception from TS follows:

Situation: Error loading referenced assembly
     Outer Exception Type: System.IO.FileLoadException
     Message: Could not load file or assembly 'ArtOfTest.WebAii.Design, Version=2013.1.1002.0, Culture=neutral, PublicKeyToken=4fc62bbc3827ab1d' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
     HRESULT: 0x80131040 (Official ID (if app.) = FUSION_E_REF_DEF_MISMATCH, Error Bit = FAILED, Facility = FACILITY_URT, Code = 4160)