W32/Acebot-A is a network worm which spreads over open network shares and has backdoor capabilities.
Upon execution the worm drops itself to the Windows system folder as a randomly named executable and deletes itself from the current location. W32/Acebot-A sets the following registry entry
HKLM\Software\Microsoft\Windows\CurrentVersion\Run\Microsoft Dianostic
so that it is run on startup.
The worm attempts to join an IRC channel to listen for commands and is also able to circumvent the firewall products Sygate Personal Firewall, Tiny Personal Firewall, ZoneAlarm Pro and ZoneAlarm.