Hi Mark.<br><br>What OS are you using?<br><br>Windows 9x reports a high CPU usage any time it's doing a PING or TRACERT (using ICMP.DLL). You can duplicate this CPU usage behaviour by using a standard PING or TRACERT and watching the CPU useage spike during this period. I tried pretty hard toget Ping Plotter to work around this behaviour, but as yet have had no luck.<br><br>Windows 2000 and NT don't have this problem - they report normal (1%ish) CPU useage while there are outstanding traces.<br><br>Basically, under 95/98, you'll see 100% cpu useage any time the "Querying" word is up on the lower left corner. You'll probably not notice any performance slowdown during that period (because windows is just waiting for a response - and not actually doing anything), but it is a bit disconcerting to see the CPU useage spike like this.<br><br>I'm hoping to add a different implementation of ICMP echo requests soon - that should stop this problem from happening (in addition to a few other things).<br><br>If this doesn't describe the problem you're seeing, let me know. It's possible I've missed something and it actually is Ping Plotter's fault.<br><br>