when i connect to my project it says:
This solution is offline. [Team Foundation Server: https://tfs.codeplex.com/tfs/TFS12]
Team Foundation Server https://tfs.codeplex.com/tfs/TFS12 does not exist or is not accessible at this time.
Technical information (for administrator):
The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel.
this error continue to appear from 2 days, what can i do to fix it?