Hello,
I am having this problem for over a month. I installed Exchange 2003 with sp2 about a month ago. BTW, this is the only server I have. I changed "A" record and "MX" record from the website of my Domain hosting company. I even talked to their tech support to confirm the changes I made. Yes, I can send and receive emails fine within my office network, but OWA doesn't work. When I type "mail.mydomainname.com/exchange", I receive "page not displayed" message. I have a Netgear router and it's not blocking any ports and I verified with my ISP that port 25 is not filtered. But when I ping from Telnet, the result indicates that port 25 is filtered. I need help.