Bob, I'll bet you're right. Another helper suggested the file could be protected in some way, which is something I did not think of.

I did find a workaround. I copied the offending column to an entirely new workbook. That by itself carried the offending hyperlinks (for SOME of the entries, but not all of them, even though they all looked like hyperlinks; I still haven't figured that part out) into the new workbook. But then, when I selected the entire column the "remove hyperlinks" choice did appear and it did work. So I then recopied the corrected column back over the original column in the original workbook and I'm good to go.

Thanks for your thoughts!