To update my initial problem report, I have a kludgy workaround that works for my Windows 10 computer. Still I want to insist that this is a serious bug that Intuit should have fixed by now.
When you initially click on the "File" drop down menu you may notice that nothing happens. That is to say, no File drop down menu appears. Another responder to this problem report links this problem to having downloaded financial data from a brokerage firm.
Wait a bit after the first click attempt -- at least 30 seconds. Then try a second mouse click. At this point you may eventually see (if you look closely) a very dim drop-down menu to the left of the Turbo Tax window. It is hard to see because its transparency level is quite high. Looking closely at the drop-down menu you may see the menu choice you want to select. Click on that item and you may find Turbo Tax rewards you with the desired behavior.
To summarize the kludge, keep trying, be patient, and scrutinize the screen for a very transparent File drop-down menu.
