I recently ran the "Rebuild Permissions" option with drupal 7 admin/reports/status
I didn't realize at the time that Node access permissions were disabled. Anyways, after running it, I can no longer edit roles or ACL (among other things). I get Access Denied. The user has admin rights, and I've doubled checked all that. I even tried to create a new user, but it doesn't work.
Also, I can add a new ACL Role, but cannot edit it after creating it.
Furthermore, each panel in the dashboard shows access denied with user login.
It turns out that my civicrm.settings.php file had the ip instead of the domain name. That caused the issue.