I have been using a Horner Electric SNP adapter cable (HE693SNP306AX) with an RS232 to USB adapter for the last 6 or 7 years to communicate between a Windows XP laptop and GE series 90 PLCs using LogicMaster LM90 DOS based software. I have never had any communication problems with that setup. My XP machine died and I now have a Windows 7 Pro machine with a virtual XP machine running on it. The LM90 software works fine in the virtual XP environment but I cannot establish communications with any of the PLC processors. Is there a com port driver I need to download? I have spent the last 5-6 days trying to get this to work with no success. Any help with this will be greatly appreciated.
