I can insert comments into the worksheets of most of my Excel 2000 files at any time. But some files in which I have already inserted comments, I cannot insert a new comment in any of the file's worksheets. When I select and then right-click on a cell that is formatted as "General" there is no "Insert Comment". And if I select and right-click on a comment there isn't any way to edit it.

I've checked in Tools>Options>View and verified that "Comment indicator only" is enabled. I can't find any other option about Comments in the Excel Help file.

I've noticed that "[Group]" appears after the filename in the Title bar (see attachment) in files that have the problem, so that must have something to do with the problem.
1. How do I get rid of the [Group] in the title bar?

2. How can I enable Comments in those files?

Attached Images

Excel Group in Title Bar.jpg (83.0 KB, 11 views)

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* HP Pavilion Desktop 510-p114
* Windows 10 Home 22H2 19045.6575