Help! Categories and tags gone from all my sites

Hi, im using wordpres 2.8.4 for 8 sites at a shared hosting plan.

Today on all my sites al the categories and tags are gone. It says no categories.

The categories and tags are still present in the admin panel but when I try to assign a post to a certain categorie and add tags and update the post, it still remains without categories or tags. Writing a new post and creating new trags and categories also doesn’t work. The post is published without categorie or tag.

Any suggestions?