registering pc on network

well, i have a loose rule of thumb to take error messages at face value until evidence to contrary. so i would first make sure domain user account had login rights to domain. but pretty sure you will not find problem there. but it is the 'using existing pc name' that would have me doing this for a test: change the name of one of the new computers slightly, add x or something to the name, see?...then have it rejoin the domain. then i would go to server, logon as administrator and double-check the domain user(s) account properties to make sure had logon rights on new computer(s). if i don't find a domain user management utility then i am in a workgroup, not a domain. i would go back to the test client computer and check the user accounts (control panel/users). and if not exist then add user account(s) using exact username and password as on server. then and add to usergroups per your preference.

The computer may have the same name, but in AD, even if you joined the computer properly to the omain, it isn't the same computer.

Therefore, if you have specified that a user can only log onto specific computers, in this instance the user's account can only log onto a computer that doesn't exist anymore. You will need to go back into the properties of each user's account and delete and re-enter the entries in the "Log on to..." section of the Account tab.