I just realized that all of our contributors cannot edit pages. When logged in as administrator, there is no problem. But when logged in as contributor, as soon as I click 'pages', I get a blank screen. This happened on version 3.4.2, so I upgraded to 3.5 to see if it would solve the problem. It didn't.
Contributors can do everything else OK, they just get a blank screen when the click 'pages' or 'view pages' in the admin.
I already deactivated all plugins, but I still got the same blank white screen.
Any ideas on what might be happening and how to solve it?