Problems with Filters

Other than the unused ones outsie the print area, no.
There may be blank columns if that has anything to do with it.

Hi!

Missing columns (i.e. entirely empty: not even a heading) will act as a barrier if you depend on Excel to delineate your data area. But that doesn't explain your problem.

I have, however, replicated your behaviour by blanking row2 (below headings), selecting one of the column headings and then activating Autofilter.

Alf

Like i said, there were no rows completely blank.
Oddly enough, out of 6 people who tried opening the file after the issue was discovered, 2 of them had no problems. I had one of them save the two files and now the problem seems to have disapeared.
I now know what to do if it happens again, but still have no clue how to keep it from happening again.

Thank you for your time.