I had an issue of TFS web access resulted with TF31002 error along with HTTP 404 response:
TF31002: Unable to connect to this Team Foundation Server: https://tfs/tfs. Team Foundation Server Url: https://tfs/tfs. Possible reasons for failure include: – The name, port number, or protocol for the Team Foundation Server is incorrect. – The Team Foundation Server is offline. – The password has expired or is incorrect. Technical information (for administrator): The request failed with HTTP status 404: Not Found.
As indicated from the error, the TFS application tier DNS name cannot be resolved. In this case the server was configured with SSL only access, with HTTPS binding to a FQDN.
Adding an explicit server name in the application tier configuration file has resolved the issue. Open for edit:
C:\Program Files\Microsoft Team Foundation Server 2010\Application Tier\Web Access\Web\web.config
Add the server FQDN address:
<add name="https://tfs.company.com/tfs" />