Our TFS setup is such that clients are authenticated using the BASIC mechanism, not Integrated Windows Authentication (IWA). This is due to the multi-domain environment where not all domains fully trust each other. The 2012 R2 version handled TFS very well, both on the Test Studio (TS) and Test Executor (TE) levels. Both these clients prompted with authentication dialog at right times. The picture is different with 2013 R1. While the new TS still works as expected, the new TE in the remote mode (when connected to the combination of storage and scheduling services) does not. When we schedule a test list for execution and check the 'use TFS version ...' option, TE never prompts for TFS credentials and consequently chokes on executing the list. Interestingly, this problem doesn't happen in the 'local' scheduling mode.