Step 1: Open the Windows Start menu and enter regedit into the search bar.
Step 2: Right click on HKEY_LOCAL_MACHINE and select Find.
Step 3: Search for OEMBackground, which should be in Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\Background. If the key does not exist, add a new DWORD value with the name OEMBackground.
Step 4: Double click on the entry OEMBackground, and change the value from 0 to 1.