Question: Hi there I am having a bit of a simple task problems.
We have pretty simple configured MS server 2012 in our school.
The thing is we want to deny access few PCs from ONE user so our students can only access library PC with their OWN account as we want to monitor their actions.

I have one user (library\_user) and this user should NOT be able to log on to three specific PCs. 

One way I thought is to delete the Domain User group to specific computers and create a new group with all users EXCEPT library\_user user. But there are so many users on "Domain Users" group that it would take a long time to add all users manually. 

Would this be the right way to get this done? Thank you

Answer: 
So finally my issue has been resolved. 
I have found another laptop with the same model, I replaced SSD and copied my data.
Thank you guys for your time and suggestions.
I know this is old but ,will leave this here for anyone who has this problem, under windows 7, I thought the enclosure was faulty at first, the problem is the new ssd comes with gpt partition table, which win 7 can't read, the solution was I borrowed another laptop with win10 under disk management changed format to MBR, win7 can now read the disk.