What is a quality SMTP server that can be downloaded for under $25?

I am looking for a SMTP server that we can use for outgoing mail that permits a high volume (1,000+ per hour) without getting blocked. It could be downloaded on our machine or run online, but cannot cost over $25.开发者_如何转开发 Isn't there a good open source solution? I haven't been able to find one yet. Thanks.

Well, there are even free SMTP servers that can send a high volume of e-mail.

The problem is not in sending them, the problem is in delivering. You see, SMTP is a best-effort store-and-forward protocol - the e-mails are passed from one SMTP server to another in hope that it gets closer to the adressee's mail server (and usually it works). However, this also means that your message can be rejected or dropped anywhere in this chain of servers - or by the recipient. Once the e-mail leaves your network, there's not much you can do about it. In other words, it's not your server blocking the e-mails, but the servers it will be passing the mails to.

This question may be a useful reference for your problem; see also this article for some tips that will help your e-mail get delivered.

For that ammount of email, probably any server will do just fine. The problem is not to be blacklisted as a spammer. Jeff Atwood has a good blog post on the subject.

I personnaly would recommend Postfix or qmail, but that just me ...