Following comes to us from Deepak Mittal.
Users may see this error in VS:
TF31003: Either you have not entered the necessary credentials or your user account does not have permission to connect to the Team Foundation Server at https://servername/tfs Click to Use different credentials link below, or ask your server administrator to add the appropriate permissions to your account.
Resolution:In case this KB is installed, there are few possible solutions in case you face TFS connectivity issue: o Disable kernel mode authenticationo Disable compression on IISo Force client to disable compression 1. Disable compression at IIS level as mentioned in below msdn article:http://technet.microsoft.com/en-us/library/cc730629(v=ws.10).aspx 2. Disable kernel mode authentication at IIS as mentioned in below msdn article:http://technet.microsoft.com/en-us/library/cc754628(v=ws.10).aspx 3. Disable the compression on TMG for TFS:ForeFront TMG -> Web access policy --> HTTP compression --> Set it to disabled 4. Upgrade your TMG environment to 2010. 5. There’s a workaround from the client side for this issue, which is to set the registry key to not enable compression for this client (so client will not send Accept-Encoding header). So compression is part of the cause here, and it involves the HTTP API. Set the following registry key: Key = HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\12.0\TeamFoundation\RequestSettingsValue = (EnableCompression, REG_SZ, False)