Troj/Agent-PL is a backdoor Trojan for the Windows platform.
Troj/Agent-PL contains the functionality to access the Internet. When first run Troj/Agent-PL copies itself to <System>\msbnc.exe.
The following registry entry is changed to run msbnc.exe on startup:
HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon
Shell
explorer.exe <System>\msbnc.exe
(the default value for this registry entry is "Explorer.exe" which causes the Microsoft file <Windows>\Explorer.exe to be run on startup).