Why Can I Not Edit Content in My Drupal Site?

We can log on to the admin and alter user accounts. We can alter permissions. We've checked permissions and they appear to be correct. We've rebuilt permissions and cleared the cache. We've also optimized the database tables. We cannot edit any content (this is true for all roles). We are not getting errors. The fields are just uneditable. We called Inmotion and they said everything looked fine -- no errors, no hacks. We were able to edit until 4:20 Eastern time.