[PatrickH]

I'm having the same problem almost every time I start OmniFocus: start up, force quit, start up 2nd time. After I force OmniFocus to quit, during the second startup I get a dialog box asking whether I want to restore the windows from my last session. I click no and then OF opens and works fine.

I began having this problem immediately after I installed Lion. I suspect it's due to Lion's Saved Application State.

Twice I tried closing all OmniFocus windows before quitting. Both times, the next time I opened it I had no problems. Also, one time I deleted the OmniFocus file in the Library>Saved Application State folder, and it subsequently opened without a problem.