@rkmcswain
In cases like this (if the other items don't resolve the issue) where its been working
I always recommend to disconnect for your network/internet and then launch the product. Run it for a few days in off-line activation mode. Once the product is running, plug or connect back to your network. I know its a band-aide fix but every time I suggest it, the user is back up and working.. 
In this off-line activation mode you have 30 days before it requires activation again..
But this work-around only works if the application has already been run once and the license activated.
Mark Lancaster
& Autodesk Services MarketPlace Provider
Autodesk Inventor Certified Professional & not an Autodesk Employee
Likes is much appreciated if the information I have shared is helpful to you and/or others
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