John, thanks, but...
I've looked everywhere I can think of in Firefox. MSIE is fine, and up until yesterday, so was Firefox, which I've been using for at least a couple of years. Something changed, and I'm not aware of doing anything to change it. I can accept cookies with no problem. It just bins them whenever I close Firefox. Maybe it's an anti-nastyware program that updates automatically, but I don't know why it would zap Firefox cookies and not MSIE ones.

Oy.