Before upgrading to Windows 10, did you uninstall your McAfee Subscription or disable it at the minimum? It is recommended to do so during any major upgrade. You can always contact Technical Support at no cost to you. https://service.mcafee.com/webcenter/portal/cp/home/contact
Quite possibly one of my Colleagues whom runs Windows 10 , may very well add to this discussion.
All the Best,
No this is a new PC - on my old W7 PC it still works fine.
Please clarify whether you're trying to login to TrueKey with Master Password or creating a new account with TrueKey. Also do you notice a wheel spinning for a long time.
Marking this thread as 'Assumed Answered', since no further feedback. Locking it.