I have search all internet support sites including MS, but could not found solution to our POP3 problem. Users are not able to retrieve messages using Outlook Express from exchange server. Details are as following. 1 One Server is installed by Nawasi with Windows 2003 Standard Edition with Exchange 2003 Standard Edition, (New installation). 2 All security patches are installed on the Windows Server, except Windows 2003 SP1, Service Pack 1 for Exchange is also installed. 3 POP3 Service is running and also enabled in the Exchange 4 POP3 access is only working on the Server, I am able to connect and retrieve messages on the Windows 2003 Server by connecting to the local POP3 port of the exchange server by using Outlook Express. 5 But if the 5 workstation try to connect and retrieve messages from the Exchange server 2003, using outlook express, it is not possible. 6 To further diagnose the problem, I have telnet the exchange server IP with POP3 110 port address, I was able to logon by using USER and PASS, and I was also able to use LIST command to retrieve message list, but the problem start when I try to RETR message. It just hangs and does not retrieve message. 7 Five Workstations are able to connect and retrieve messages by using MS Outlook 2003,IMAP and HTTP, the problem is with POP3. 8 I have checked the properties of the POP3 Protocol under exchange administration tool, all the local LAN IP has permission to connect. It is important for us to use POP3 applications. Regards, Thank You,