Your problem more or less seems to me like a security setting in the user's browser.. or the java version\ OS, the user is using to VPN..Try getting teamsite added to the trusted sites... browser settings to default...also get various diagniostics information from the user like JVM version, OS, Browser and Browser version, OS and OS version
Thanks for the response,One thing we did notice with the user is that he's able to get to our dev instance of teamsite & do edits. But not in QA or Prod. This rules out browser settings on his end.