Data -> Group -> Group does not work on A Sheet

I have a large Excel workbook and one of the worksheets that had Data -> Group (under Outline) turned seem to have lost the groupings I setup.

I selected the columns to be grouped again and went to the Data Ribbon Bard then the the Outline Area and selected Group -> Group and nothing happens.

I tried a few times just in case, but nothing. Found it does not work for rows either. Other sheets in the workbook have the data grouping. I then copied this worksheet to a blank workbook, saved it and tried again and still Grouping do not work.

I selected all the rows and columns and did a few Ungroup type things "just in case" and tried the group again, but nothing.

There are no hidden sheets or other selections that i can find.

This is in Excel 2016 (not Office 365) x64.

Any thoughts or ideas what do try next?

thanks

Alan

wow, thanks!!!

I never realized you could turn that off worksheet by worksheet.... Not sure how it would have gotten changed.

thanks

I also updated my Office/Excel version to 2016.