Blocked by administrator

[Isabelle Graham]

We have a few people who are getting the error "access to network is blocked by the administrator" 
when trying to log in to the agent in Windows. So far as we can tell they should pass the checks and 
be allowed in, but this error is persistent (removing the agent and re-installing doesn't help).
Has anyone seen this before? Is there a known fix?

CAM 4.1.2.1
Agent 4.1.3.2
--
Isabelle Graham
Information Security
American University