Reset forgotten Windows Administrator password
1. Boot the server from a Windows installer ISO 2. Select "Repair" and "Troubleshooting" then click to open a command prompt 3. At the command prompt type:
move d:\windows\system32\utilman.exe d:\windows\system32\utilman.exe.bak copy d:\windows\system32\cmd.exe d:\windows\system32\utilman.exe
4. Reboot the server 5. When at the login screen click the below icon 6. This will open a command prompt, at the command prompt type:
net user <username> <password>
7. Type "exit" to close the command prompt
You should not be able to login to the administrator account with the password you just set