Hello
I am experiencing something similar. Here are some additional details of my
installation. I have an Exchange 2003 server configured for RPC over Http
(Single server installation). The affected client machine (1 user) is running
Office 2003 on a Win2K workstation. She can receive mail, but sent mail never
gets out of the Outbox. This started about 2 days ago.
Also two days ago, I configured a laptop running Office 2003 and XP SP2 to
retrieve her mail using RPC over HTTP. The timing of this installation and
the send problems with her Win2K workstation would seem to be a smoking gun.
The short version: I can send mail from her mailbox via OWA, as well as from
the laptop using RPC over HTTP. The original installation on her Win2K
workstation will not send messages - they stay in her local Outbox (the
exchange server never sees them ). The Send/Receive operation indicates no
errors.
Is there some incompatitibilty with Win2K workstation and RPC over HTTP? I
have done the same thing with no problems with other users, but their laptops
and their workstations were all runiing XP. This is the first time I've done
this using the different Windows OSes.
I would also appreciate any input on this.

Thanks
CM