In our college we have a active Alumni community, All of their AD username and passwords is active. recently management told me to block all the Alumin users access to college computers, which means when they are on campus they should not able to login to any of the computers in the campus but they are only allowed to use online portals which are integrated to Active Directory. All of this Alumni users are kept under a OU called "Alumin 2006-2013" which is around 3000 users and all of the computers in our campus are under a OU called "College Computers".
Please help me with a best solution to block these Alumni users, i think GPO based solution will be best don't know which is possible or not, i need experts solution on this case.
We are using only one Domain Controller which is running on windows 2008 x86 SP1.
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