Might be a set up issue with how your SAS VA is configured, like a wrong address or your permissions. It might be a temporary network system issue.
If you attempt to connect at a different time, like hours later, and you connect then it is likely a network issue.
Do others in your class have the same connect problem? That would point to a configuration issue if so. If you are the only one with problems and it persists you'll need to contact whoever is your SAS admin to make sure the installation you use is configured properly.