[snip] Unless the email is coming "from" somebody the recipient knows/trusts, then you're going to get marked by them as a spammer -- which will report back to some of the lists marking you as a spammer. [/snip] But is it not a problem sending from the SMTP server thedomain.com using something else then the email thename@xxxxxxxxxxxxx? I am planning to send from an existing email from the domain. So even that I send from thedomain.com SMTP server I should to set the FROM and REPLY TO to the person who is referring? Our main idea was to send the email from the author of the book as it comes from him, but that is maybe not a great idea? So I am in the middle of two suggestions: 1. Make sure that the email is in the domain that you are sending from 2. Make sure that the emails is from the referring persons email so it won't be marked as spam at their point. This is what I got from "Rick". What are you thoughts on this? [snip] when you do a dns lookup (from a machine not on the same network) on the ipnumber of the sending mail server does it show a name? if you do a forward lookup on that name, does that resolve to the (same) ipnumber? the answer to the first part must be "yes", and ideally the second will be "yes". if the first is "no", then don't bother sending from that machine until that issue has been dealt with. sending html substantially increases the probability that your messages will be tagged as spam. certain things will increase that probability. your point "2." is mostly irrelevant. an smtp server simply needs to be configured so it is not an open relay. that is generally the default configuration (of any MTA that's worth using), and is achievable without smtp auth. [/snip] Best regards, Peter Lauri www.lauri.se - personal website www.dwsasia.com - company website -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php