Recently I have had a lot of E-mail messages not sent, with the error code 4.4.7. I have changed all my timeout settings and number of concurrent messages. I don't think that did anything? Finally, I just re-started the Exchange 2003 server and all seems to be ok now. I have run into this re-start solutions, a couple of times now. Is it possible that Exchange is getting some corruption???? Any thoughts ? thx