Till now, the only solution I could think of was to move the mailbox to another store. When I did that, it would be OK temporarily. But the problem still keeps happening again and again.
After it takes too much time trying to receive the first e-mail (some start receiving and then stop; the number varies from user to user), the user receive the following error message in Outlook:
"Task 'mail.xxxx.xx - Receiving' reported error (0x8004210A): 'The operation timed out waiting for a response from the receiving (POP) server. If you continue to receive this message, contact your server administrator or Internet service provider (ISP)."
I turned off all the computers and tested for one user and it is the same. As I told before, it is happening for certain user accounts, not for one person this time and for someone else the next time. The antivirus is Trend Micro Server Protect and Trend Micro Scan Mail for MS Exchange. I have tested these products before and I had never have had any problems.
I have tried downloading the e-mails using different computers for the account and different Internet connections, but the result is the same. Please help.
This could be a number of issues. One could be a routing or firewall configuration issue, and, depending on how the client routes to the given Exchange server, one path may have port 25 blocked. A retry may choose an alternate route and succeed.
Another reason might be networking issues. Any number of issues could be present, including out-of-spec cables, too many hubs, duplex issues, (e.g., the client computers are not reliably negotiating the same duplex mode as your IP switch). To troubleshoot, check the System and Application Event logs for network interface related messages. Also, open a command prompt on one of the machines, run a "netstat –s" and note the number of retransmitted packets. Run your Send/Receive and re-issue the "netstat –s"; if there is a significant delta, suspect your network configuration.
Another diagnostic approach is to log the conversation for a while on the POP3 virtual server. To enable logging, reference the Microsoft Knowledge Base article 299778. Please take heed of the warnings for exhausting system resources and enable logging for a controlled period of time. This also requires restarting the inetinfo.exe service after resetting the logging through the registry changes (or an Exchange server reboot).
MEMBER FEEDBACK TO THIS ASK THE EXPERT Q&A:
I was having the exact same problem with a completely identical setup -- same OS and antivirus, etc. I found the following article on the Microsoft support site and it fixed my problem completely: POP3 client stops responding (hangs) or times out when you try to download messages in Exchange 2000 Server and in Exchange Server 2003.
Do you have comments on this Ask the Expert Q&A? Let us know.
This was first published in March 2005