When you click the "Hide" button, sd4hide makes specific, temporary changes to a registry setting. In essence, it "blinds" SafeDisc v4 by masking the virtual drive letter so that the protection system can no longer detect it. To the game, only the physical disc drive appears present, even though the data is being read from a mounted image.
When a user mounted a game image to a virtual drive, they would launch sd4hide.exe before starting the game. The tool performed a few exclusive functions: sd4hideexe exclusive
The variant is rumored to use a specific hooking technique that bypasses the standard NtQuerySystemInformation call, which is how Task Manager populates its list. By hooking this call and filtering out the specific Process ID (PID) of the target executable, the process becomes a ghost in the machine. When you click the "Hide" button, sd4hide makes