Thanks for your reply. I cleared everything out and no change in the messages.
I should have included this info: Because of multiple disrupting factors in last few weeks, I have over 3000 email messages in my box. Is this a factor? (Normally I have less than 100--and less that 1% of 2048 MB)
That definitely sounds like the culprit
If you have the option, can you clear out ones you may not need to keep and see if you keep getting the same message?