[djbaxter]

Look at the headers. That will give you the reason.

There may be several:

- mailbox full
- mailbox temporarily unavailable
- mail server did not respond or timed out

That's why action is NOT automatic - you're supposed to insert a human administrator between the bounced mail and the response so you can determine what the most appropriate response should be.

I find at various times ALL forum mail to AOL or Hotmail or Yahoo will bounce with one of the above error message - then a day or so later it will all ve fine again.