is it pointing to ProWin21 under 21Data?

Yes. Box says: Homebase-File Open Error

Cannot Locate c:\prowin21\21data\abar9612.21ifile. Would you like to browse?

If you open up your computer's file explorer and open up your ProSeries folder, is there a data a folder there and does it have files in it?

Yes!

In the upper left corner your homebase view, click on the "open file" symbol and see if you can open a file from there.

Open File does not work either. All the other years, both before and after 2021, function properly! In fact, 2 weeks ago I was able to print a return from a 21 Data File…

Have tried going to your computer start menu and selecting ProSeries and then clicking on tools - repair updates?  If not I would try that.  If that doesn't work I would uninstall and reinstall ProSeries.  If that doesn't work I would flip a coin to see whether I call support or I retire. 😉

Thanks IRonMaN: Repair Updates didn't work either. I appreciate your expertise.

I think I'll take you advice and retire DURING my telephone travail with Support...

Good luck.  If they fix your problem, please come back to share what the issue was so others can maybe be helped in the future.

If you could open up a new one there is a little light at the end of the tunnel ------------------ just watch out for trains coming through that tunnel 😜