Question : SMTP via my isp

I have A win 2k server with iis installed.
I have created a website using asp.net and require it to send out an activation email.
I have also set up the 2k server as a virtual smtp server to relay the emails to the outside world.
This works fine from my development machine (at work) as the smart host is set up as my works smtp email server.
However, I cant get access to this server from home (where the website is hosted), so I have to use my isp's email server.

The firewall is configured to allow outgoing on port 25
I have tried setting the smart host to their email server (on the 'Default SMTP Virtual Server Properties' page, 'Delivery' tab, 'Advanced' button) and then set up the username \ Account and password for both 'Basic Authentication' and 'Windows Security Package' (on the 'Default SMTP Virtual Server Properties' page, 'Delivery' tab, 'Outbound Security' button), but the emails don't get past the Queue folder.

What have I missed?
Anyone got any suggestions?

cheers,
m3

Answer : SMTP via my isp

No there is no way to run a mail server. You have to use their servers.

They do this to prevent you from having a open relay mail server which can be used to send out spam.

Though why don't you use their mail server?