Mail SPF configuration?

Question

THE SITUATION: I have ONE e-mail account per domain. I use e-mails such as [some-alias]@[one-of-my-domains-name]. (server: mail.[mydomain]:[secure port] My registrar (OVH) is different from my web host (Arvixe). My hosting plan is a mutualised .NET hosting. When I want to reply with one of my aliases, I use Mozilla Thunderbird 'Identities'. (Login = concrete domain mail account, FROM: 'the alias e-mail'.) (And yes, this is very efficient to avoid getting spams and unwanted mailing lists.)

THE PROBLEM: For some recipient using some spam protection services, I constantly get the error:

Remote server replied: 550 Blocked by SPF ()

HINTS/QUESTIONS AND IDEAS IN SEARCH FOR A SOLUTION

• a friend said I have to configure the TXT spf record of my domain.
• using different webmaster tools sites to get DIG info, I never get infos about the 'TXT' record. So I'm not sure: Should I edit this record on the side of my domain registrar or in the side of the hosting ?
• Current on my registrar's side the record reads: v=spf1 a:mail.[mydomain] include:mx.ovh.com ~all and on my hosting's side it reads: v=spf1 a:mail.[mydomain] ~all

THE BIG QUESTION: How can I solve this ?

Thank you for your help

Answer 1

Solution found: - I actually had to set the SPF or TXT (I set both at the same value) record on the hosting's side. - I used check-auth@verifier.port25.com , which a mail service to checking if your e-mails are passing some anti-spam filter. - The reply given by check-auth@verifier.port25.com made me understand the Source IP/HELO hostname were not mail.[mydomain] but [myhostingserversubdomain].arvixe.com here what my SPF and TXP spf records look like:

v=spf1 mx ptr:[thesubdomain].arvixe.com -all

(I think 'mx' is really not necessary in my case.)

EDIT : Slight improvement:

v=spf1 ip4:[[thesubdomain].arvixe.com IP] ptr:[thesubdomain].arvixe.com -all

mx removed since in my case the mx servers have nothing to do with it. "ptr" requires DNS lookup, so I added the direct IP. I left "ptr" in case the IP changes (since it's managed by my host).

Answer 2

Your SPF record is a statement that the IP(s) sending the email are authorised to send email for your domain. In your case I am assuming you're actually sending through the Arvixe servers. The records should be set in the TXT record for your domain at the registrar (ovh).

So in this case you need at your registrar (ovh) to edit the TXT record for SPF to read:

v=spf1 mx a:mail.[yourdomain] include:spf.arvixe.com -all

Note: The modifiers on 'all' vary - +,-,~,? - and specify whether recipients should consider the tests conclusive and reject mail or not. There's a great (very thorough) howto on SPF here: http://www.zytrax.com/books/dns/ch9/spf.html

What is a bit unusual is that the recipients are rejecting what should be an inconclusive SPF record (e.g. default = accept). One of the core problems with email is that there will always be edge cases where recipient servers exhibit odd behaviour - I hope this helps in this case.