Recently we had to retire one of our exchange 2010 servers and replace it with another one. As soon as we did this a large number of users started getting prompted for login credentials. What I discovered was that their outlook anywhere setting was enabled and auto configured when the account was set up on their machine. We can't turn this off at the server level because we have a large number of laptop users that need this feature when they are on the road. I tried to disable it though GP but couldn't get it to work. Is there somewhere else I can tell Exchange or Outlook to not auto configure our client computers?