outlook 2003 smtp timed out error 0x8004210A - no network activity

[Michael Hennessy]

I've got a group of identically configured OL2003
machines, some of which are intermittently, but
frequently, unable to access their SMTP server.

Testing has show that its not the MTU issue, and pop
traffic works fine, as does all other internet traffic.

When the ol2003 wont send email, network captures of
packets show that there is _NO_ activity at all coming
from the machine in question - it obviously thinks its
opened a connection to port 25 of the SMTP server, but it
has not.

The real kicker is that at this time, a manual telnet to
port 25 on the same smtp server, from the same client
machine, will work.

It looks like outlook has lost connection to its tcpip
stack somehow, but only for smtp traffic..

This problem is about to cause a downgrade of a fair few
ol2003 machines, so if anyone has any ideas of how to fix
this it would be much appreciated.

MH

 

[Michael Hennessy]

An update to this - running outlook under the dependency
walker I've established that on the occassions when the
smtp succeeds, wsock32.dll and ws2_32.dll are being called
from inetcomm.dll, but on the occassions whe it fails they
are not.... so the problem looks to be internal to outlook
and/or the operting system/network support dll's.

......