Problem with Sending mail by PHP and SMTP server

I'm using winxp and apache as the web server.And i have installed the SMTP server on my computer. And the php.ini has modified. But when i using the send mail function in PHP, it returns such error:

Warning: mail(): SMTP server response: 550 5.7.1 Unable to relay for zerog@hkem.com

Is there problem?How can i slove it?By the way, it can send mail to the user on the local machine.Can anyone help me?

This is a problem with your SMTP server setup...not PHP.

Do a google search for "550 5.7.1 Unable to relay for" (with the quotes). Lots of information there.

Thanks for your reply,Matt.

There is such a lot of information about the problem. But a little of them is useful.Besides,some links have also changed.Can you tell me which web site teach me how to config the SMTP server?

Which SMTP server are you using?

Thanks for your reply first.
I'm using the SMTP server in the IIS in the win XP.But i'm not using IIS as the web server.I'm using apache as the web server.

Thanks for your reply first.
I'm using the SMTP server in the IIS in the win XP.But i'm not using IIS as the web server.I'm using apache as the web server.

Unable to relay is a safety feature built into your mail server. This prevent spammers from using your mail server as relay. There has to be a section in the config that says what IP can send mail

Thanks for your reply first.

I have already configed the SMTP mail server and allow a ip to relay, but the same problem occurs. Can anyone help me?

did you configure 127.0.0.1 and localhost?

yes,i have configed the ip(allow relay) as 127.0.0.1.Is there any thing that i havn't done?
Besides,I also try to use Argosoft mail server to try the mail function. But the same problem occurs. And something special is that if it can only send the mail to the account on my computer(user set in the mail server).What can i do to solve this problem? Can you briefly describe the process of setting up the SMTP mail server in the IIS of winxp? By the way,thanks for your reply.

Ok if you goto
Properties dialog of your SMTP virtual server |G o to the Access tab | Click the Relay button | Add a record for 127.0.0.1, and your real IP and localhost

Did you do all three?

thanks your reply first.
Actually,i did all the three things that you've saidalready.But it still can't send the mail.

Ok, I am at a loss on this one. I must bow out. Have you tried linux

Thanks for your reply.
Sorry,as i'm using win xp as the os,i can't install linux and check it.....
By the way,i want to ask if there is any affect if i install the router and send the mail?

In the IIS (Admin Tools - IIS)
Right Click in Default SMTP Server
Properties
Acces Tab
In Relay Restrictions click Relay
Choose -> All Except the list below
OK - Apply
Stop and Start SMTP Server.

Work with me.

paulo@cotonet.pt