Spammers ruined email and it can now be pretty hard to pass some spam filters. Of course, 95% of your emails will make it through if you do it yourself, but the last few % can be hard to get.

I recently started sending through Fastmail.fm for our website and it's been working fine. I simply setup sSmtp on our servers and everything that is sent through Sendmail is now relayed through Fastmail.

Another company I've considered is authsmtp.com. I haven't tried them, but their pricing seems to be very reasonable. The reason I didn't go with them is that I already had a Fastmail account (and I hate paying twice for the same thing ;-) )

We did Gmail before, but setuping Postfix to relay through them can be a major pain (mainly because of the way they authenticate). Fastmail (and I assume authsmtp) was a no-brainer.

Another thing that will help delivery tremendously is SPF. Make sure to set it properly (with hard fail if possible, ie: -all).

Good luck!

EDIT: Looks like for the Enhanced service, they allow 2000 messages per hour. Cost $40/year.

http://www.fastmail.fm/pages/fastmail/docs/pricingtbl.html

EDIT2: Looks like that's inbound :(

Hard fail can send people who use email forwarding to their spam folders.

In terms of specifics, I like qmail. In terms of spam management, there are lots of things to do. First and foremost, have daily monitors on all the major email providers. Get on all their feedback loops. I've found that contacting them with problems is annoying, but does work if you are following all their guidelines and are persistent about it.

Current stats say that our % of users who have signed up that make it through email confirmation step is about 22%.

Around 33% or so of our signups have yahoo.com addresses, and only about 12% of those manage email confirmation.

It is similarly bad for hotmail. GMail used to be quite good, but has slowly gotten worse over time.

I'd be very curious to know if others are measuring these things, and how you are doing. Feel free to contact me directly as well.

There are a few things you have to get right (DNS including a PTR for your IP, SPF and now DKIM, RFC compliance in your server and configuration), but once that's done, bounce rate will be nearly as low as the quality of your list allows. Hitting the spam filters isn't all that bad either--assuming your message isn't spammy on other counts.

One other thing to be wary of: Sending to the same domain many times in rapid succession. Be sure you're not sending more than one or two messages at a time to Gmail or Yahoo or Hotmail (or any single server). So, randomize the list, and sleep for a second or two between each send, or something, to insure that there are pauses.

Oh, and at least Google's spam filters are reputation-based (and probably many others are, as well). The looser you play with the "opt in" requirement, the more likely you are to be flagged as spam by your recipients. It only takes a few to get your future mailings dumped into the spam folder. At that point your server itself is poisoned from sending to that destination for a while. So, make sure your recipients actually want what you're sending them.

In my new services, I did have issues originally, especially on Gmail. So there was an initial ramp up with spam issues on the majors. But like I said, after following all their rules and then persistently hounding their support staff to investigate, I've gotten past their filters.

I've worked on several business that had to send confirmation emails (via our own servers), and the figures were never anywhere near as bad.

If there is any way that your users can benefit from signing up other users (e.g. if you run an MLM site), you might want to look into whether your stats are not being falsified by a few users submitting vast numbers of email addresses into your system.

You can benefit by signing up other users, but this is not a very often used feature. It's not an MLM site, but a subscription chess service.

We track signups by ip and by browser cookies, so we're reasonable sure these are distinct people. Since we switched to the freemium model, there is little incentive for people to make duplicate accounts now, so I was hoping to see activation go up.

We do domainkeys and SPF and I have gone around the block with hotmail two times already.

We send approximately 25k emails a month, the bulk of which are sending out confirmation emails to people that signed up, and then a thank you for those that confirm. The rest are forgot password emails and invites.

http://blog.fastmail.fm/2007/12/05/sending-email-servers-bes...

Did you do anything in your installations to address that problem? If so, what was it?

If permission based is OK for your needs, AWeber is top of the line (www.aweber.com)

Here's a similar discussion: http://news.ycombinator.com/item?id=190633

As long as your SMTP server is reasonably secure (you can run simple blacklist tests on it from various sites), you shouldn't get caught by IP-based spam filters, and then it's just a question of whether your content looks spammy to your recipients' mail systems. That's unrelated to how you're delivering the email, so it's the same problem no matter what you're using to send.

That said, guaranteeing 100% success with the delivery of e-mail is pretty much impossible. You just can't control what the recipient has installed in terms of mail client, spam filtering software.

Can anyone suggest a solution that allows tracking of opens, bounce backs, and other standard metrics?

I'm not being glib. Really ask yourself if it's necessary to email this information to users. If I get email from a company and I don't want it, I don't like your company. If your company has information that you think is important to me, notify me next time I log in. Let me determine whether or not it's important.

A) be sending from your own dedicated IP address (so that spammers sharing your IP address don't cause all your email to go to spam) and

B) work with a deliverability provider such as ReturnPath or Habeas.

Authsmtp seems pricey in comparison.

You just need to set up the Google Apps service manually; everything else (including creating accounts, new addresses, sending emails, creating email aliases, etc.) is fully "automatable" via their API; with wrappers available in Python, PHP, C++, Java, Ruby, Perl, and more....

That's pretty low for any service, and a total hassle to create a bunch of fake user accounts and keep track of how much they've sent today while round robin-ing around "as many accounts as I hope I'll need today".

It's good to note to that you can do aliases for each account too