My client is running Server 2003 SP1 with Exchange 2003 SP2 and I am experiencing some strange symptoms, At least 2 users, including Administrator cannot send email from the outlook client and or OWA to any external recipient. The affected users can send and receive internally as well as receive from an external sender. I have checked and compared the mailbox rights in AD under each user, to the known good users and I can't see anything that would cause this behaviour? Any suggestions are appreciated. Michael

When you say they can't send email, do you get an error or does it just sit in a queue?

Hi Joel,Thank you for your replyNo error message, and nothing appears in the queue at all, but all sent messages do appear in the sent items folder; this is the case for both the Outlook 2K3 client and OWA...a strange one!Also if I send one of the affected users an email from an external account, and they reply, the reply message go through; these symptoms aren't adding up, but they are consistant with at least 3 users!