I have about a 50-50 success ratio getting VMSpc to talk to my ECU on a Cat C7 engine. It will run fine hibernating each night and restarting each morning on one trip, then next trip I get "comm port failure" every time. Start VMSpc turn ingnition on, turn ignition on then start PC and bring up VMSpc makes no difference. I've verified it's the correct comm port as well. Any bright ideas? VMSpc spec is 2.3 Build 2 running on an IBM R51 and WXP. Thanks Todd Butler