I had this same issue on my Windows 10 desktop and found an easy fix that may or may not help others, but here it is for what it is worth.
I was prepared to call TT support when I noticed that a flash drive that I had used to store bank statements on was still residing in a USB port. Removal of that drive immediately corrected the problem.
In my case the problem was that my system was not playing nice with TT, not with TT itself. So, check your system for any changes that may have been made just prior to your problem.
