This may sound like a silly question, but my experience with Exchange is very limited:
We run a Windows SBS 2003 server with Exchange. A member of staff requires POP3 access to his emails on his mobile phone. I have configured the phone to access our Exchange server and the emails download to his handset fine. Problem is, he can't send emails. Our ISP's SMTP server will not accept SMTP traffic unless its coming form our network router's public IP address, so we can't use this.
How can I configure our exchange server to relay SMTP traffic from outside of our network? Is this possible, or would I need to contact our ISP to ask them to allow SMTP traffic from other IP addresses?
Any help would be appreciated...