Troj/Bdoor-IS is a backdoor Trojan which allows a remote intruder to gain access and control over the computer.
When first run Troj/Bdoor-IS copies itself to <System>\spool.exe.
The following registry entry is created to run spool.exe on startup:
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
Print Spooler
<System>\spool.exe