Troj/BushTro122 is a backdoor Trojan which will run in the background as a server process, allowing a remote user (using a client program) to gain access and control over the computer.
It copies itself to the Windows directory as SERVER.EXE and to the Windows System32 directory as system.exe. It also creates the registry keys
HKLM\Software\Microsoft\Windows\CurrentVersion
\RunServices\System32 = Windows System32\system.exe
and
HKCU\Software\Microsoft\Windows\CurrentVersion
\Run\SERVER.EXE = Windows\SERVER.EXE
This causes both copies of the server process to be run automatically each time the computer is restarted. Troj/BushTro122 will also attempt to notify the remote hacker when the affected computer is accessible.