I'm scoping out a project where users will be able to query a database and have various information fields returned to them. They will then have the opportunity to submit comments about that information.

To reduce comment spam I'd like to incorporate e-mail confirmation i.e.

1. User has to provide a valid e-mail address along with the comment.
2. Upon submission, server attempts to e-mail the commentor at the provided e-mail.
3. If the e-mail goes through, the comment is accepted.
4. If the e-mail does not go through, the comment is rejected.

From brief research on the Web it seems it's not too difficult to send e-mail from .NET (this would be running on Windows Server 2003 with the SMTP server enabled). However, I don't know how possible/practical it is to:

- Get/read the result of the call that sends the mail
- Does that result (if available) indicate success/failure?
- How long does it typically take - is it practical to wait for the response before indicating success/failure to the commentor?

Any experiences/ideas/comments welcome. TIA.