This helped me!
After working on a document (brochure from a template) in Pages for some time, suddenly I "don't have permission"...huh?! I uninstall, reinstall, plists, blah blah. Nope. I repair permissions. Nope.
Making a new account, logging in and using Pages a little, (even though the pages in that new account is a trial) then logging back in to my own account, actually worked. No idea why. Hope it holds!
ps I'm using 10.7.5.
Message was edited by: dinesy