Requirement
Windows 2012 (whatever version) installation CD/DVD
To reset the password on your Windows 2012 server complete the following steps:-
Boot from the Microsoft Windows Server 2012 DVD
From the Windows Setup menu, click Next
Select Repair your Computer
Under Choose and Option click “Command Prompt”
At the command prompt type
| ren d: \windows\system32\utilman.exe utilman.old |
Enter
Then type
| copy \windows\system32\cmd.exe d:\windows\system32\utilman.exe |
Enter
Close the command prompt and click Continue
The server should now reboot and present the logon screen.
Here press the Windows key and u
A command prompt windows comes up
Type net user administrator Password123 (or whatever complex password you choose)
| net user administrator Password123 |
This will set the password to Password123 (case sensitive)
Now having set your new password, once logged in delete the utilman.exe file or others can change the password at any time using the Windows key + u !