Outlook 2002 will NOT send some email

[Harold]

I have a situation that does not make sense to me. On one
machine, the operator (member of power users group) can
send/receive email without problems on Outlook Express.
However, the operator wants some of the features of MS
Outlook so it was installed and setup. Here is the
problem. Emails can be received without difficulty in
Outlook. Send works perfectly if the file is a new one
created by Outlook. However, if reply to sender is
selected, invariably, the file will not be sent. If the
original email was inside the intranet, there is no
problem sending it.
I have searched everywhere for a setting that looks as if
it will cause this without success. Anyone out there have
a solution.
Hardware config is P4 2.8GHz with 1 gig DDR 400 mem. Clean
install of win2k pro sp4 generic OEM on machine. PC is a
workstation on an NT 4.0 sp6 DC controlled network (NO
Active Directory). Security level has been dropped to
minum to see if that affects it.
Note: another user on a similarly configured machine that
was originally Win2k sp2 and upgraded to sp3 and then to
sp4 DOES NOT have the same problems.

 

[Harold]

I found a solution that looks promising.
It appears that M$ set the MTU (Maximum Transmission Unit)
to 1500 bytes in Windows 2000 Professional. This was hard
coded and not shown in the registry.
The same parameter in Windows XP is now set (again hard
coded and thus not visible in the registry) to 1454.
Followig the instructions outlined in Microsoft article
315008, I was able to resolve the problem for Outlook by
setting the value to 1454.

Once again M$ has put the shaft to us and blamed it on
anybody they could (Linksys routers).

Verify the truth of this by searching for 0x800CCC0F on
the Microsoft knowledge base.

How do I send them the bill????