Troj/Agent-GTW is a Trojan for the Windows platform.
When run Troj/Agent-GTW creates the files:
<System>\<random characters>ex.dll - detected as Troj/Agent-GTW
<System>\<random characters>.sys - detected as Troj/Agent-GTW
Troj/Agent-GTW then registers the DLL as a system service so that the Trojan is run at startup.