Is that still even a thing?  Most computers don't come with CD players anymore.  Wait, it could by a 5 1/4" floppy disk.  Or the newer state of the art 3 1/2 inch floppy disk.

And why ask other tax preparers?  Contact ProSeries sales (I'm guessing).

@dascpa You're showing your age. 😀

Feeling it too....

If you have a disc, open up your coffee cup holder and put the disc in and close it.  It should pretty much do its own thing.

@aybeeler You can download the CD image from MyAccount, on the Dashboard.

After logging into MyAccount, click on the down arrow next to Previous Years, then select 2021 from the dropdown menu on the left. You will then see a link to download the full CD image.