Several threads have talked about odd problems in Windows that were
EVENTUALLY traced to a bad MTU setting. This is a little known, but widely
seen, Microsoft problem. While Windows SHOULD detect MTU properly, it often
does not. This problem is inconsistent, and often hard to find. Google
"windows XP MTU 1492" for a good hint. A good example is
http://www.annoyances.org/exec/show/article04-107 which shows a fix
requiring no additional software. Here is the same fix, with pictures.
http://www.winguides.com/registry/display.php/280/ One that also talks
about VPN and Dr TCP. http://help.expedient.net/broadband/mtu.shtml
The reason for this post is a quick answer for easy reference and searching.
I also recommend inclusion in the documentation.