OL2003 "your microsoft exchange server is unavailable"

[ScottS]

I just upgraded from Office XP to Office 2003 Pro (OS
WinXP). I attempt to launch Outlook and receive "your
microsoft exchange server is unavailable".

I can ping the server attach to the WEB based exchange
client (the same machine), also I can log on locally to
the server, and map drives to it - so there is network
connectivity. However, neither outlook will nor the mail
configuration on control panel will log into the exchange
server.

 

[clive hammond]

Check your DNS, you may be able to ping the server but i believe OL
uses DNS to resolve the server name. If your DNS isnt correct you may
be trying to resolve your server name on the INternet, and you get
your error message.

CLive

 

[Keith Hill]

I am having a similar problem. I can ping the machine by its DNS name. I
can tracert it (5 hops). I can even telnet to port 25 on that machine and
get a response to "HELO". But whenever I try to connect, I type in my
password then it goes out to lunch for about 2-3 minutes. Then it comes
back says:

"The connection to the Microsoft Exchange Server is unavailable. Outlook
must be online or connected to complete this action."

What's weird is that with my laptop (same setup Outlook 2003 on XP SP1) over
the same home network, I can get into the exchange server just fine. I
should mention that I use the Nortel Extranet VPN software to access the
exchange server. Are there any log files generated by Outlook that might
shed some light on this failure to connect?