Ensure email delivery with email server

Question

I have set up an email server for my own company and the domain has never been used. However, I noticed that some of my emails have failed to deliver.

I made sure all the settings on the email server are correct (SPF, PTR...) and I checked that the IP is not blacklisted any where.

What should I do to ensure delivery? Anything else I should try?

Answer 1

Each mail provider, especially the big ones like Gmail, Yahoo, AOL, Hotmail and so on has their own spam filtering rules.

In addition, all of them have their own internal blacklists that are not visible to outside users these are not regular RBL blacklists you can see.

The only solution that I found is to get yourself an email box on one of those or all of them and try to send from your server to this mailbox.

In some cases, you will see the result that will end up in the spam folder. If that happens check to see if there is an explanation for this in the mail headers.

Answer 2

There is no 1 thing you can do to ensure delivery, however one thing which could well help you is to send your emails to another server which uses spamassassin (or similar) which documents how it tags your email, and make appropriate adjustments. [ Experience shows that a lot of players who have "big servers" either use Spam Assassin in the background or an equivalent engine which looks for similar things.

Another solution you can use is to "make it someone elses problem", and relay outgoing email through your Internet provider.

Also, particularly if you are just starting out, you will find that some providers will limit the volume of emails you can send in a limited period. Luckily these limits tend to get larger as they see legit traffic from you, but it takes time. (Sometimes the solution here is to send email directly, then if it fails relay through your ISP - either that, or wait as typically they don't stop you sending, they just delay you and make you retry).

Also, set a reasonably aggressive initial retrys (60 seconds, then 5 minutes), which can help deliver emails faster if the provider is doing greylisting.

Also, check your logs - they should provide information as to whether the provider is accepting and discarding your email, or not accepting your emails at all.

Answer 3

I suspect I have not the same setup as you since I am using Google Apps, but I had problems with my emails being marked as spam until I setup DKIM.

It might be worth giving it a shot, unfortunately I cannot help you with how to set it up if it is not within Google Apps.

Answer 4

• when you set up an e-mail server an entirely new domain most of the giants like gmail and hotmail will mark mails received from your domains as spam.(i have experienced it).
• This can happen even if your text contains simple text. (no images or html) .
• I would suggest writing a mail to google and microsoft and notify them about your domain.
• Request the people who receive these mails to mark them as not spam.