baffled_in_york;11034117 wrote:
x-mailer: PHP4
Are you serioulsy using php4 (FOUR)? If so, stop doing so immediately and upgrade to PHP 5.5. The php 4 lifecycle ended several years ago. At the beginning of 2008 iirc. Moreover, I personally don't see a reason to include an x-mailer header. Just format the email correctly and there should be no problems.
baffled_in_york;11034117 wrote:
I have a contact form that generates an email. If the customer has an Hotmail account (that I put in the Reply-To part of the header)
You have completely missunderstood the purpose of the reply-to header. That value is the address to which the reciever of the email (i.e. the hotmail user) is supposed to send his or her reply. The "to" header field is what designates the reciever.
That is, you send your mails to "to: recipient@theirdomain.example.com"
They reply to whatever address you specify in "Reply-to: me@yourdomain.example.com"