On Feb 19, 7:19 am, Denise wrote:
Hi! I have a spreadsheet originally created in 1998 that has properly
formatted headings and no empty columns or rows on the sheet we want to
filter. I have unhidden any rows or columns that were idden - there is no
protection on the sheet or the workbook.

What am I missing? What is keeping this data from autofiltering? The
option is just grayed out.

Is the worksheet/workbook protected? If the contents of the worksheet
or workbook are protected, changes that can be made are very limited.