Network problems are preventing connections to the exchange server

[Husam Al Jabi]

Hello,

Strange problem:

I have users who are on a remote network. Their
mailboxes are on an Exchange 5.5 server in a different
country, linked by VPN. They are all configured to work
off-line and synchronize their mailbox to send/receive
mail. One user is having an issue of getting this
message: "Network problems are preventing connections to
the exchange server", as well as other synch failure
messages constantly. She is even having the same message
and is not able to send when trying to work online with
the server.

When user logs on to a different machine and tries to log
on to the server (using connect option not work offline),
her send/receive is fine, albeit slow. This suggests an
error with her Outlook client rather than network
connections or server mailbox issues. All ping and
trecert requests from the user's machine to the server
are fine and indicate that the server is in fact
reachable, no problem. She is not having a problem with
any of her other Network Based applications (e.g.
Internet/Intranet).

Any suggestions please?

Thanks.
Husam