To be honest, i'm facing a problem like that this week.
I'd check one thing, make sure make sure, that "C:\Program Files (x86)\Avaya\IP Office\OneXOutlookPlugin\AvayaIPOfficePlugin.vsto" is there.
The issue I have on the laptop is that the folder is never created, and when I manually copy this entire folder over the the laptop and manually add the add-in; I get an error with .wav files that of a folder I dont even have in the working PC's directory. lol, it's bananas. I think i'm going to wipe the machine, install outlook and then install the plugin and work as bare as I can.
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