Taken from the hide desktop guide for Mame HKEY_CURRENT_USER \Software\Microsoft\Windows NT\CurrentVersion\Winlogon Look for a string entry called 'Shell'. If it is not there, create a string entry and name it 'Shell'. Set the value of this entry to the name and location of your Front-end. For Dragon King, the shell entry may be "C:\MAME\The Dragon King.exe" or wherever your Frontends executable is located. To repair this if anything happs, boot into safe mode, go into regedit, and change this value to "explorer.exe". When you reboot, you will find that you enter windows, and not your frontend! Simple!