That’s exactly what I felt like in this situation. I was working in Excel 2010 on a workbook with multiple sheets when I suddenly couldn’t interact with the Insert or Data menus (they were entirely greyed out), I also couldn’t interact with my PivotCharts at all.

I spent half an hour scouring the Internet and reading that it may be to do with my Sharing or Protected Workbook options, but my workbook was neither shared nor protected.

The Solution

I had inadvertently selected multiple worksheets, *clicking* on a single worksheet doesn’t deselect the multiple worksheet selection – here’s where the bad design causes confusion. You need to shift-click on a single worksheet to deselect the others, and resolve the problem.

Update 1 (07/04/13): I’ve had a lot of people commenting thanking for the above – you’re welcome! Some people have found that this hasn’t worked for them, thanks to commentor “Laci” who has posted another solution which seems to cause the same behavior:

Solution B:

“Excel Options”
“Display options for this workbook”
“For objects, show”.

Update 2 (08/04/13): If neither of the two solutions above work for you, commenter “maurita” has another solution if you’ve found your data options are unavailable in Excel

Solution C:

You may have enabled “Track Changes”, to undo this go to the “Review” tab and click on the Track Changes option and deactivate it/accept the changes.

P.S. My favourite comment so far has to be:

17 – Margaret (September 28th, 2012):
“I found this just moments before committing Seppekku… Thank God.”

Keep the comments coming people, especially if none of the above work and you find an alternative solution. Rob.

Update 2 (12/01/16): Yes, these solutions are still going strong! I still receive lots of comments from you guys saying that one of the solutions either from here or in the comments fix your issues with Excel 2010, 2013, 2016, Solution D added:

Solution D:

It might be a shared Workbook, so you’ll need to disable sharing. Click on the “Review” tab, then “Share Workbook”, then, under Editing uncheck “Allow changes by …”