A client of mine has a network with 4 computers on it. Their ISP is Bresnan Communications (http://www.bresnan.net).

Here a sequence of events that happened a few months ago:

- Everything working fine

- Randomly, one day no computers on the network could send email using Outlook Express with and error that said, "The connection to the server has failed." The error number is 0x800ccc0E. The following command fails when typed of the cmd prompt: telnet mail.bresnan.net 25. All other Internet functions worked great.

- Any computer could send email when connected directly to the cable modem.

- I made them replace the router with a Linksys WRT54GS With SpeedBooster. Presto! Problem resolved.

- Everything working fine for several months.

- Last week, randomly no computers on the network can send email using Outlook Express with the same error as before. Any computer can send email when connected directly to the cable modem.

- I also have Bresnan as my ISP. I have a DLink router and can send email and typing telnet mail.bresnan.net 25 works like a charm at my house.

I upgraded the firmware and disabled the router's firewall. My main test machine on the network has no software firewalls installed. Bresnan said since it works fine when I connect directly to the modem that it is Linksys' problem. Linksys was very polite but not very helpful; they tried adding port triggering and forwarding settings that I didn't have to have before and wanted to place the computer in the DMZ. This is not useful when multiple computers need to send email....

Any ideas ?