Troj/Bdoor-S is a Trojan for the Windows platform.
When executed the Trojan will copy itself to the file
C:\Windows\System32\Drivers\System.exe and creates the folllowing registry entry in order to run automatically when Windows starts up:
HKCU\Software\Microsoft\Windows\CurrentVersion\Run
PrintSpoolSv = C:\WINDOWS\system32\drivers\System.exe
Troj/Bdoor-S allows a malicious user remote access to the infected computer.