Hi there, Situation: Our hosting server 10.0.0.1 Our Ns1 and Ns2 10.0.0.2 and 10.0.0.3 Mailserver 192.168.0.1 Domain: test.com DNS Settings: mail.test.com. A 192.168.0.1 pop3.test.com. A 192.168.0.1 smtp.test.com. A 192.168.0.1 test.com. A 10.0.0.1 webmail.test.com. A 10.0.0.1 ftp.test.com. CNAME test.com. www.test.com CNAME test.com. test.com. MX (10) mail.test.com. test.com. NS ns1.test.com. test.com. NS ns2.test.com. 10.0.0.1 / 24 PTR test.com. User A send an e-mail from the domain test.com to email@example.com using a PHP script. Normally the server should look at the MX10 record and forward the e-mail to 192.168.0.1 The server picks up the e-mail and thinks to itself: The domain test.com is a local domain so I am not forwarding anything and keeps the e-mail local, so firstname.lastname@example.org doesn't receive his e-mail! I always hosted on Linux working all fine, but it seems like Windows doesn't care about DNS?! Anyone has a solution?