I tried your suggestion but it didn't solve the problem  : (
But here is a new wrinkle I think...........it locked up late last night so I closed it up and went to bed ..........got up this morning and everything was working fine again....so I start a new session and it's all going good then I go to render a pic, and it gets about a third of the way done and ...BAM!!   not responding........ this is the first time it has happened "during" a render it usually just locks up as soon as you click on "ok" in a dialog box.

I hope this additional info is helpful