Fixing DNS of your mail service to avoid delivery fails

Fixing DNS

If you keep getting your letter back with this message:
"support@felenasoft.com SMTP error from remote mail server after end of data: host mx.felenasoft.com [111.22.33.44]: 550 5.7.1 Sorry, it is a SPAM filter. Please fix your DNS! You need to add TXT and SPF entries into your DNS for yourdomain.com domain confirming that sample.domain.com [123.234.45.56] server is allowed to send emails. You must list all your SMTP servers. Sorry, only -all is allowed (but not ~all or ?all). Details: http://xeoma/en/contacts/dns-fix/ . If you are using gmail, add also (before -all): include:_spf.google.com (or other servers similarly). For example: @ IN TXT "v=spf1 a mx ip4:123.345.56.67 -all" . Current error details: yourdomain.com: No applicable sender policy available."

Here’s what you should do:

If an intermediate is used to send mail rather than your corporate one, you need to find out their domain name that always have an up-to-date list of IP addresses like other mail servers do, like:

Google:
include:_spf.google.com
redirect=_spf.google.com

GoDaddy:
include:spf.secureserver.net

Yandex:
redirect=_spf.yandex.net
redirect=_spf.yandex.ru

Yahoo:
redirect=_spf.mail.yahoo.com

Mail.Ru:
redirect=_spf.mail.ru

and so on.

Suffice is to put the right name after the include, and it will work uninterruptedly, without any spam.

What does it mean and why should I do it?

Most services, including gmail, although accept mail, but don’t necessarily actually get the messages get to a receiver. These messages can get to a spam folder since they don’t have the SPF entry, and neither sender or receiver is notified about it having been filtered out.
So if a receiver isn’t checking the spam folder regularly, the message can be easily lost.
That’s why you should add the SPF entry.