server programs

hi all,

recently i tried to set up a server on a windows platform (i know this isn't the best, but i don't have any courage to start working on linux right now ).
it's an apache2 webserver with php 5.1.1 and mysql 5.0.
atm i'm looking for a smtpserver( i've checked out this post), but i can't seem to find one, and the one i've allready found i don't seem to get them configurated.

i tried postcast smtp and arGoSoft mailserver (freeware) so far, but both give an error while trying to send email.

the postcast couldn't send testmails to my email address
the arGoSoft mailserver gives no error, but when i'm trying to use it in combination with php, php gives he following error:
Warning: mail() [function.mail]: SMTP server response: 551 User not local. We don't relay in E:\Documenten\Server\Scripts en Templates\testmail.php on line 6

does anybody knows a beter mailserver or knows what the problem is?

many thanx in advance
UnrealEd