Background image on logon screen os common issue with pre-installed servers, for example from Dell. That makes accessing those systems via Remote Desktop painful and slow (it happenes that serer is shipped to location, racked and stacked, and then whole configuration take place remotely). By default background bitmap from logon screen is sitting in C:\Windows\System32\oobe\info\backgrounds, so you can put your own logon screen background or if you don’t want to have any (just system default) you can follow instructions below and remove background from logon screen.
- Start Registry Editor (REGEDT32.EXE).
- Locate and select the following Registry subkey: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\Background
- Double-click on the OEMBackground value and change it to 0
- Click OK.
- Exit Registry Editor to save the changes.