Posted by Gordon Burditt on 11/18/09 11:44

>I never had problem with this PHP page with mail() function with at
>least 5 different servers, but email sent through the server of this
>"T" company tends to get blocked by spam filters. I tested with my
>different email accounts and these are the results.

Is it possible that other customers are originating SPAM from this
company, and it has been blocked because of that? If this is the
case, getting off of private block lists may take decades or be
entirely impossible. About the only way out is to find a provider
that is not SPAM-friendly.

>* The mail is delivered to the "Inbox" of my AOL account.
>* The mail is delivered to the "Bulk Mail" folder of my hotmail and msn
>accounts.
>* The mail is delivered to the "Spam" folder of another account of
>mine.
>* The mail is not delivered to any of my two university accounts.

Will any of the filters tell you WHY it was considered SPAM?
SpamAssassin, for example, can put a header in the mail giving
detailed scoring for why it thought something was SPAM.

>One thing I noticed is that this "T" company hasn't setup the "From"
>section, unlike the other servers that I worked with before, so the
>mail is coming from "Nobody" <nobody@________>. I suggested the tech
>person of the company update the "php.ini" file, but he doesn't admit
>that's the issue. I tried manually adding the From with PHP coding
>with "$headers," but it didn't make any change.

One check that is commonly made by mail servers is to start to send
a bounce message to the From: address, stopping short of actually
sending a body. If sending the bounce fails due to not having a
mail server to send it to (no MX or A record), or the destination
server denies having such an address in response to RCPT TO:, the
mail is rejected. In other words, the server for __________ domain
had better accept:
MAIL FROM:<>
RCPT TO:<nobody@__________>

Servers that reject MAIL FROM:<> (that is, all bounce messages) will
find that there are a lot of places that the domains they serve
can't send mail to.

Gordon L. Burditt

[Back to original message]