Now, i have experienced one issue of smtp sending mail via outlook express.
The email server is linux, and resides behind firewall, the outlook express client also lives behind a firewall.
I caught the packets both on client and server side.
It shows that after tcp handshaking, none of tcp packets can be received from each other any more. It is very strange. Client is sending tcp ack, server side is resending syn/ack again and again.
Can you give me an idea how to figure it out?
I paste the packet trace here for your information.
Please unzip it and change the .doc to .pcap and open it with wireshark.