Hi, John.
This is a rough one to troubleshoot. It sounds like there's some kind of issue with something running on your machine, since the error *did* occur with PING at the same time as PingPlotter.
I'd start out by switching to ICMP raw sockets and see if that changes things - maybe there's just an issue with ICMP.DLL. Then, maybe try running PingPlotter on a your neighbor's machine.
We have a couple of articles that touch on this topic a bit:
http://www.nessoft.com/kb/37and
http://www.nessoft.com/kb/22See if that gets you an ideas.
It does seem like a local PC issue rather than a router issue, based on the "General Failure" message. Are you getting similar errors in PingPlotter (it will show up above the upper trace graph)?
- Pete