SPF issue

[Adrian]

Hi people. I have AMS Enterprise edition installed on my mail server, and I've been having trouble with some SPF related filtering.
I have a couple of known clients that every time they are asked for a read confirmation, their confirmations get caught by the SPF filter. If they send regular emails to any account on my AMS, their emails reach the receipient with no problems.

I've tried putting those domains and their IP addresses on the "SPF Safe IPs" list, but I still don't suceed on getting them, they are still stopped by the filter.

Any ideas? If you need any additional information, please ask.

Thanks to all.

[Code Crafters]

SPF filtering works by checking if the IP sending mail is on the sending domain's SPF record and therefore authorised to send mail for that domain. Normally only mail servers hosting the domain's mail are authorised to send mail for the domain. Read receipts from a mail client like outlook should use the account's login details to send mail via a hosting mail server the same as if it were sending mail directly to you from that account. If this happens, there should be no difference between the two which likely means that this isn't happening correctly.

Check your SMTP logs (accessible via the start menu program group) to see what IP and domain are used by the read receipt then check against that domain's SPF record to see if the IP is authorised to send the mail. If you have a normal mail transaction from the same account check what the difference is in the logs to find out what's going wrong.

[Adrian]

Hi, Chris.
I've done what you suggested. The IP address from where the read receipt is sent is different from the regular emails sent by that domain. I don't know why.
Anyway, just adding that new IP to the SPF safe list solved the problem.
Thanks for your help!

[sillyme]

You may also need to consider what service the mail sender is using. I had a situation where a clients lawyer started using Microsofts business email service. In tracking down why it was getting blocked I found that there was nearly no way to tell where in the world email was going to come from.

The sender was in New York the destination in cincinnati. I checked several emails and the source server would sometimes in the US, sometimes europe and one even passed through Amsterdam, which raised concerns with me. When I checked I found other people had the seen the same thing. To me that is a big security problem, especially when transmitting legal documents. I do not know if Microsoft ever addressed that but it is something to consider.