I had this same problem over the weekend - the update was getting stuck at 10%. I tried applying the manual update and run all of the Windows scans in previous Community articles, but none of that worked.
I found out that the recent security update from Windows 10 is blocking Turbotax from being updated.
I had to go into Window Updates History (push the Start Button, search "Windows Updates" and click "Check for Updates", then click "View Update History") and click "Uninstall Updates". Then Uninstall the recent update (KB4601319).
By deleting this recent Windows update, it allowed Turbotax to Update.
NOTE: DO NOT FORGET TO REAPPLY THIS WINDOWS UPDATE AFTER YOU FILE!
