In the event you forget/ lose/ neglect to write down the administrator password on a Windows machine (this is confirmed working on Server 2012 but should work on most versions) below are the steps required to reset the password.
Reset the Password:
- Boot from a Linux key or attach the server’s disk as a secondary/ external drive to a computer.
- Rename c:\Windows\System32\Utilman.exe to something (e.g. Utilman.old)
- Duplicate c:\Windows\System32\cmd.exe and rename the new file Utilman.exe
- Reboot the server
- At the login screen hit Win Key + U to bring up the Utilman.exe (now really cmd.exe)
- At the command prompt type the following:
net user administrator NewPassword
- Login to confirm working
Once new password is set, undo changes made:
- Reboot back into the Linux key or attach the disk as an external again.
- Delete c:\Windows\System32\Utilman.exe
- Rename c:\Windows\System32\Utilman.old to Utilman.exe
- Reboot, at the login screen Win Key + U should now bring up the Utility Manager
- You should now be able to log onto the machine with your administrator/ NewPassword credentials.