The SMTP Service included in IIS is not a mail server, it is a mail forwarding agent for mail-enabled Web Applicatons. It can send and receive mail and relay mail from other SMTP hosts.

If you work on code at home, on your own server, then port it to the hoster via FTP, TS or some other means you may need to have the SMTP service setup. Most of my apps use some kind of email feedback and it can be a real hassle to write Javascript send mail and then add code that checks if I am on a dev server or not. The following directions will help you set up the server and then depending upon your agreement with the hoster you can either send the mail or just have it dump to the mail queue. Either way you can easily simulate that portion of your application without writing special code or finding some other work around.

These instructions are for one virtual server even though you can host multiple smtp virtual servers.

1. Right click on myComputer and select manage.
2. Expand the Services and Applications node of the tree.
3. Select Internet Information Services
4. Right click on SMTP Virtual Services
5. Select the Delivery tab of the property sheet
6. At the bottom of the screen select the Advanced button
7. In the Masquerade domain enter "imposter"
8. In the Fully-Qualified domain name enter your servers domain

   Example: xena2.webpyrfect.com

9. In the Smart Host textbox enter the IP address of your remote Mail Server.

   Example: x16.x58.x92.x35

10. Leave the two checkboxes unchecked when using imposter account
11. Everything else should just be left as default
12. Close the property sheet
13. Right click on Domains.
14. Click on new and select Remote
15. Enter the domain name for the ISP

    Example: ispdomainname.com

Once you have it configured you can stop the service so nothing really goes out; but now when you test the email it will go to the queue which means that it is working.
The queues for the smtp are located at c:\inetpub\mailroot and you can check the queue for messages waiting to be sent.