The problem: I enabled the forum module one day looking to start using it on my site (it had been disabled across many upgrades from Drupal 4.7 to 5.1 to 5.2), but I noticed that categories were unavailable for selection (absence of the category drop-down) when making a post despite there being forum, forum containers and corresponding forum vocabulary in the admin area and database tables (i.e., TIDs, etc.). Consequently, posts were not placed in any forum containers/categories.
The solution: After coming across this article: http://www.nzwhost.com/article/how-fix-broken-drupal-forum I realized that I had somehow lost the entry for Forum in the vocabulary_node_types table in the Drupal database. All the table has is the fields VID and Type. In my case, I only had to restore two pieces of info that were missing from my vocabulary_node_types table.
SQL query:
INSERT INTO `vocabulary_node_types` ( `vid` , `type` )
VALUES (
'1', 'forum'
);
Ta-da! Took me hours to find a useful article after searching for every variation of "no/missing drupal forum categories" in Google and on the Drupal site. If your case differs, check the link for further hints, but many roads seem to lead to vocabulary_node_types if your forum categories are missing. I bet this applies to other content types if you mess with their entry in the vocabulary_node_types table.
Comments
Thank you thank you WOOHOO So
Thank you thank you
WOOHOO
So very grateful for this post. Finally I can get some sleep. Thanks you :)