Let explain that a little more clearly. My other admin tried to create a new forum. I have no idea what happened but...
When you click on "Forums", the only forums that display are the new ones he created, with 0 posts (they were given forum_id starting at 18). I have "Recent Topics" enabled on the right side and those still show all current forums (forum_id 1-8) and posts. If I click on a forum in Recent Topics, it will take me to it and I can see all the posts. But, anytime I click on Forums from the menu I get only the new ones. I checked the database and all forums, old and new are there along with all the topics. It seems like the Forums somehow lost the link to the correct forum_id. Selecting "sync forums" does nothing. Any ideas? Oh, debugging gives no error messages whatsoever. TIA.

If you go to the Newbb admin page are the forums still listed?

If so go into each one and make sure that they are set to active, all global access rights are set correctly, and all topic permissions are set correctly. Check the Categories also, same settings.

That's all I can see that would (maybe) cause a problem like this.

HTH.

No, they are gone from the admin page. Only the category remains. If I create a new forum using the same names as the old it gives them new ID numbers (of course). Is there a way change the ID number that NewBB2 is looking at when you go to the forums, because they are still in the database? Funny how the Recent Topics section still shows them and the posts.