Originally Posted by alexxxm
but that's exactly what I did!
Following the suggestion above (since there's not a tag editor for the "remove tags") I:
1) selected all books
2) used the tag editor for "add tags"
3) selected all the tags I want removed
4) cutted that line and pasted in the "remove tags" entry
then, after database integrity check and calibre restart, the  entries are still there
I tried to remove in the "Tag View", but there doesn seem to be a way
It is easy
Pick a single title with a Tag that you will not be removing
Click the Tag-Editor button next to the Tag line
now select all the tags you wish to remove.
click th icon to the Left
of the list
confirm (paste to clipboard if desired)