I have had the same issue and it turns out this was caused by windows recovery or repair.
Cause
Students power off eachothers machines as a joke or the battery's get pulled off causing windows to shutdown unexpectedly. Windows then decises it needs to run a repair and restores old files from a restore point.
When windows restores some of these files it restores and old machine account password. Machine account passwords are changed every 30 days by the client not the server. So when the computer is finished repairing and tries to join the domain with an old machine account password and windows then rejects the client and its all over.
Solution
To fix it you can disable automatic machine account password changes on all machines in the network. Note this will not be an instant fix if the machine has been on the domain for 30 days without a restore point set.
Instructions
Start Registry Editor. To do so, click Start, click Run, type regedit in the Open box, and then click OK.
Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters
In the right pane, click the
DisablePasswordChange
entry.
On the Edit menu, click Modify.
In the Value data box, type a value of 1, and then click OK.
Quit Registry Editor.
Thats from microsoft but its my first post so i cant post the link. Just google it.
Hope this helps.