I have a website that I want to allow users to bulk e-mail customers. Currently I'm using the SMTP relay to my domain's smtp server. It is possible some of these users will be sending out 5,000 - 10,000 emails at a time. Obviously the currently solution will not work.
I'm running Windows 2008 Server and can install Exchange if needed. I'd rather find another solution for this.
Any suggestions? What would be the best way to handle this?