A short time ago, I started having trouble sending email. I could send a message if it had one or two lines in it, but anything more than that and it would just hang there until the SMTP connection timed out. I thought it might be Eudora, my email program, so I downloaded and installed the latest version and it did the same thing: "connection aborted due to timeout or other failure".

Then I tried telnetting in to my SMTP server and pasting an email message into the session. Same thing: really short messages, no problem. Longer messages, the session timed out after I hit the old crlf/period/crlf to send the message.

Tonight, I upgraded Karen's computer, as it would no longer boot due to memory errors. She immediately began experiencing the same problem — which started for me around the time I upgraded my own system. Same CPU (Athlon64 3200+), same motherboard (ABIT NF8; nVidia nForce3 chipset). I went hunting, and eventually found a fix. The problem seems to stem from the onboard NIC — it's a gigabit network adapter, and we're on a 100-base-T LAN. I made the following changes to the adapter configuration (Advanced tab):

• Checksum Offload: Disabled
• IEEE802.1P Support: Disabled
• Segmentation Offload: Disabled
• Speed/duplex settings: Autonegotiate for 100FD

Suddenly, no more trouble sending email! Hurrah!