In the past, if I made a mistake with someone's e-mail address, I used to get
a message like "I'm afraid I wasn't able to deliver your message to the
following addresses. This is a permanent error; I've given up. Sorry it
didn't work out."

Nowadays, I never receive this when using Outlook Express 6.0, even though I
know a particular e-mail address is not valid, because when I send using a
web-based mail system, I get the above error message.

Any ideas? Can I configure OE to receive these messages?