Cannot connect to Exchange via VPN

Posted on 2010-09-14
Medium Priority
Last Modified: 2012-05-10
I have a weird issue with my home connection to the office exchange server.

The power to the office was off the other day for about an hour and when it came back I seem to have lost some of my firewall settings, which I restored.

I can do everything BUT connect outlook 2007 to exchange 2003 using the VPN.

VPN Connects and authenticates
I can surf the internet while VPNed in
I can RDP into the server
I can use OWA (mydomain.com.au/exchange)

But I cannot get exchange to connect.
Do I need to perhaps remove the exhange account and add again?
Question by:lawso

Expert Comment

ID: 33670736
have you checked your firewall logs in case its blocking the traffic to the server?
LVL 28

Expert Comment

ID: 33670933
But I cannot get exchange to connect.

>> The reason for that is primarily this.
Exchange/outlook connecting requires that packets not be fragemented when they are transported. But a VPN tunnel fragments and reassembles packets in other end.

What you need to do is configure your max MTU value, so that packets are not fragmented.
check digitap's guide on how to do that

I usually start with a ping of 1462 and then increase it by 5.
Better idea is to get away from VPN business and configure your outlook using RPC/HTTPS.

Test your exchange's Configuration here
Test for outlook anywhere

setup your outlook this way

Expert Comment

ID: 33671068
Can you ping the exchange server.  What do you mean you lost some of your firewall settings?

My initial guess is that you are trying to access the exchange server via and external  ip address and not an internal one and that RPC via http is not enabled.  I will need more information.

Accepted Solution

GridLock137 earned 1000 total points
ID: 33671196
hi lawso:

make sure you're not in offline mode, check it and then uncheck it. do a ipconfig /flushdns then an ipconfig /registerdns while connected to vpn, wait about 10 minutes or so and then disconnect VPN and reconnect to VPN. open outlook and see if the connection is re-established. could be a DNS issue since you lost power, you might have something old chached on that PC at home. also is that PC part of your domain or just a standalone pc?

Author Closing Comment

ID: 33680298
Strangely the simplest solutions are sometimes the best
Thanks to everyone for their responses.

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