I haven't wiped them both out, but before upgrading I wiped out the Plus directory, rebooted, and tried the install again.  I'll give it a try at removing both softwares, their directories, reboot, and reinstall.  I won't be able to do that until tonight (work environment and they expect me to do some 

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I did exactly what you suggested...and the same result.  msmsgr dies!  I remove plus and msmsgr is ok.