You have selected more than one worksheet. Right-click tab for the
currently active sheet (the one you are looking at) in the lower left of the
Excel window and click Ungroup.


You can also click a sheet tab that appears gray instead of white. Then,
click back to the sheet you want to edit.

So you know in the future, if you press either Ctrl or Shift when you click
a sheet tab, you will select multiple sheet, and this creates a Group.
--
tj


"Tomba" wrote:

I have a chart in a worksheet which until yesterday I was able to edit and
move around. Now I can't even select it, much less edit it. Insert Symbol,
Chart, and Comment are all suddenly greyed out all the time. On the header
bar, after the name of the file, it says [Group]. What have I done?