Tags disappeared!

Try File->Catalog->Recover. Your catalog may have been corrupted.

Annette,

I agree with the suggestion to do a Catalog > Recover.

Here are some additional points that you could investigate -

If you previously had some photos assigned with Star values for Favorites, what
happens now if you click in the box next to a star value which you had assigned
to some photos?

And --
Just to verify:

--you are sure that you have expanded the section (like for People) and the
small triangle next to the People category is facing down?

--Are you using Date (Newest First) sequence? If not what sequence? Do you have
the DETAILS box checked (next to the sequence pull down in the lower left below
the thumbnails)?