"Add Tags By List..." greyed out?

[chumbo]

Right-clicking the Tag column shows "Add Tags By List..." as greyed out? Wasn't that way before.
Any idea why that is?
Thanks!

[jupe]

You must have emptied your tag list, add some items via

Tools | List Management | Tag List...

And then it won't be greyed out anymore, or alternatively right click a previously tagged item in the tag column and select the bottom item "Add Tag to Tag List"