Cannot use the application with Mac OS X
You cannot use the application "Preview" with this version of Mac OS X
Since upgrading to Leopard, I've had occasional problems launching applications. So far, it's happened with Preview.app and Stickies.app, both on the MacBook Pro and on the Mac Pro. In both cases, a reboot solved the problem, but I've read that some folks are having the problem persist. Annoying!