Installed Omeka and now am able to “Add an Item,” but get an “Omeka has encountered an error” message when I save the item. When I go back to the dashboard, the item has been saved despite the error message. Basically, I get this message when I do anything to the item (add, edit, delete, add file). Also getting an “Omeka has encountered an error” message when I try to to view Collections. Any ideas on how to fix this?