I feel like I've sunk into a saga with no end and no one to help me except dear Curt Y. But here's what I'm concluding. The restoring or reactivation of keywords is a haphazard process at best and hardly documented, if at all. And yet maintaining your keywords is so important and takes such an investment of time! TO have this feature fail you, means that you are not going to have a very high opinion of Bridge, which is where I stand right now.
My keywords are slowly reappearing in the master list in the keywords panel without any discernible rhyme or reason, not by me anyway. Sometimes they reappear because I remembered the keyword and did a search for it. Sometimes they seem to reappear on their own (my theory is that if there was more than one keyword on an image and I searched for one of the keywords, I would get the other keywords as well. But this is only a hunch.)
If I have to bring all the keywords back into the list by searching for them, I'm in for a laborious process. I have a couple hundred keywords and I'm sure I can't remember them all.
I am currently without the ability to assign new keywords or old keywords to new images. If the keyword doesn't appear in the list, the documentation tells me that I can type the word into the box at the bottom of the keyword panel instead of checking the box next to the keyword in the list. But this does NOT connect to the keywords already established. For example, I have a keyword for "yellow," but it wasn't back in my list yet. I typed in "yellow" in the box and watched Bridge create an annexed list at the bottom of my truncated original list called "other keywords." So I now have a yellow in the first list and a yellow in the second list and not a clue on how to merge them.
Would I be correct in saying that Bridge is the ugly stepchild of Photoshop and that it suffers from neglect? It seems a rather unstable program to me, crashing out more often than Photoshop ever does. And there seems to be no documentation of the complicated but critically important business of getting your keywords up to speed after a clean install.
All help will be most gratefully received.