Can't delete layer group

[alanterra]

I have a document from which I cannot delete some layer groups. I suspect that the document is corrupted, but want to confirm before I proceed. The attached TIFF is the document. This document is derived from another document from which I deleted all the layers and all the layer groups that I could delete, leaving only the buggy layer groups. Here are some of the symptoms

• All of the layer groups cannot be deleted. (Note gray trash can in screen shot).
• There is one layer in this document, which can be deleted, which makes me think that Photoshop believes that there is another layer (or layers) in the document, which PS isn't showing me.
• For most of the layer groups, if you click on that layer group with the Move tool selected and click an arrow key you get the error message "Could not nudge the data because the group contains a locked layer." Of course, the group appears empty in PS. However if you select the bottom layer group you DO NOT get this message, yet that layer group also cannot be deleted.

Any ideas what is going on? If it is a corrupted document, what is the best procedure to fix it?

[alanterra · Accepted solution]

I got an answer in the other Photoshop group from Yves Crausaz. I'm leaving the question/answer here in case someone else has the problem and this solution is helpful to them. Yves says:

Hello, these groups are empty ????? So you probably deleted the layers that were there, but not the groups ....
Simply select all groups, Merge groups, it will result in empty layers that you can delete!