PHP Forms sending mail to Exchanger Server

timbr8ks

We ran into a problem a couple of years ago that mail sent via a Web site form could not reach email accounts through Exchange Server. They weren't going into Spam folders or being filtered out--they simply were not showing up.

We resolved this by adding -f to the mail() function. So, it looked like this:

mail($mailto, $subject, $body, "From: $mailfrom", "-f $mailfrom");

This worked. However, we've just upgraded to a new server and PHP 5, and it's no longer working. It boils down to this:

Web-based forms using mail() function
Mail recipients get mail through Exchange server
Recipients don't get the email sent by the form

Has anyone run into this issue and/or have a cure?

Thanks.

scrupul0us

have you check the mail logs on the web server? IIS should be logging mail attempts and placing bad mail in a folder according to the default SMTP server in IIS... not sure about apache TBH

thats going to be your best bet

bradgrafelman

Did you ensure that the settings in php.ini matched the old ones that worked?

Did anyone alter Exchange and PHP can no longer send mail (e.g. Exchange is requiring SMTP authentication)?

timbr8ks

The .ini files are the same, and it's happening with three clients using Exchange, so I don't think they all simultaneously modified Exchange. It's been happening only since my migration to PHP 5, although it's a new server, so there could be differences in the OS. Both are using qmail, however.

The Exchange Server people say the message is not reaching them at all, which is difficult to believe.

This remains an open (and very troubling) issue.

scrupul0us

need a mail log showing the EHLO, MAIL, RCPT transactions

bradgrafelman

Are you logging all PHP errors? Have you done a phpinfo() to verify the mail settings shown?

I'm not sure what else to suggest... how savvy are you with managing Windows Servers on a network? You might consider setting up something like Wireshark on the webserver to monitor connections between the webserver and the Exchange server; see if you can monitor the SMTP traffic and log the "conversation" between the two servers. If it's not even making any connections, yet you've double checked the host and port settings in a phpinfo() print out, make sure you're logging all PHP errors (set error_reporting to E_ALL if it isn't already) and post any you find.

timbr8ks

Thanks bradgrafelman and scrupul0us for your input.

We've checked phpinfo, and we have errors turned on. Nuthin. The forms works fine if you send to a gmail account, a yahoo account, another pop mail account. The only fail if sending to an Exchange Server.

I'm working with one company's Exchange Server's administrator to see if the mail is hitting the server at all.

As mentioned, adding the fifth parameter in the mail() function resolved this issue a few years ago. I was hoping someone else had experienced this same issue more recently and had found a fix. If I find one, I'll post it here.

bradgrafelman

Oh, I think I misunderstood your problem. I didn't realize that the e-mails were being sent to some domains but not others.

Is the Exchange server in question one on your LAN, or an outside server? It's very likely that your mail is being considered spam/invalid. Try searching around the board/Google for extra headers to add to your e-mail so that it doesn't look like a piece of auto-generated spam (e.g. MIME-Version, Content-Type, etc.).

Also, are you allowing the form to specify the "From" e-mail? If so, you should definitely stop doing this - that's an easy way to get your server flagged as a relay server and auto-blacklisted. The "From" address should always be a valid e-mail address residing on YOUR server (e.g. a domain that the webserver is authorized to send mail for). If you wanted to use the user's e-mail address, you could do so in the Reply-To e-mail header. Also try getting rid of the last "-f" parameter (or changing it to a valid e-mail on your domain as noted above).

timbr8ks

The Exchange Servers are a clients' servers, so not on our LAN. One client has said he now can see that the email is reaching the server but is being rejected instantly. I'll see if there are some additional headers that can help resolve this issue.

That said, interesting thought on the "FROM" address. I'm using info@[client's domain] for the address, and our server is not hosting email from those domains--their Exchange Servers are. I'll change the From address to see if it corrects the issue.

Thanks again for your help. If I come up with a solution, I'll post it here.