This little problem does not appear to be dangerous, just curious, and annoying. According to a bandwidth monitor I'm running, an XP Pro machine keeps banging at the network. At about a once per second cycle it keeps hitting at (Yeah I know that's loop back!) ... I have scanned with three anti-virus packages, three anti-spyware packages -- it's clean. I have removed all permissions in Zone alarm temporarily ... that didn't change it. I have studied the running processes .. don't see anything out of line there. ... A second XPPro machine does NOT show this happening.

Does anyone have any clues what might be triggering this endless cycle?