Cisco VPN Client Software conflicting with Server 2003 R2 and Exchange 2003?

Posted on 2007-10-12
Last Modified: 2012-05-05
I am experiencing a strange issue with some laptops (specifcally they are Toshiba Tecra).  These laptops are running Windows XP Professional, and are tied into a domain that consists of a Windows 2003 R2 Standard actiing as the DC, this server also has Exchange 2003 running on it and hosts email.  

The laptops are setup to access a Cisco PIX 501 using the Cisco VPN Client Sofware.  For some reason, there is a problem occurring that if the Cisco VPN Client Sofware is loaded on to the Toshibs laptops (does not matter which one), it causes a conflict with trying to access any exchange mailbox through Outlook 2003.  Basically the conflict is the simple matter of not being able to open or access the mailbox, it acts as though it can't speak with the Exchange Server.  If I uninstall the Cisco VPN Client Software from the laptop, everything is fine, the problem completely disappears.  

I have tried different versions of the Cisco VPN Client, and so far nothing has proven to work.  I tried versions 4.6, 4.7, 5.01, etc.  So, so far the solution is to leave the Cisco VPN Client software uninstalled from all my laptops.  This is not a viable solution though because now they cannot access the network through the VPN when they are taken off-site after hours.  

What I'm trying to determine, or see if this might be an issue, if there is some sort of conflict with Sever 2003 R2, and Cisco VPN Client Software.  Or maybe it's an issue with Exchange 2003 Server and the Cisco VPN Client Software.  This has to be one of the most confusing issues I have seen in a long time. Maybe it's an issue with the Toshiba OEM Windows XP Professional version?  I have not heard of such a problem before.

Thanks for your help.
Question by:Krocodile
    LVL 79

    Expert Comment

    The problem manifests itself simply by installing the VPN Client software, not after launching the VPN tunnel?
    The only thing I know that the client does is maybe change the MTU on the system from default 1500 to 1300. I've used several different laptops with multiple versions of Cisco VPN client all in a Windows2003 R2 domain with no problems at all.
    And access to Exchange mailboxes is the only thing that is affected? Not mapping drives, printing, web browsing, or anything else?
    Have you tried with any other type laptop except the Tecra? Maybe something specific to the Bios on the Tecra? Try updating the Bios?

    LVL 9

    Expert Comment

    It's a routing issue.
    The cisco client is going to change your default gateway, in most cases, so that your use the "internet connection" at the office you are VPN'd into.

    Also, it could be that both the remote and local networks have the same subnet, ie your IP at the local office is and an IP address at the remote office is also

    Do this
    Type CMD
    Type route print
    post the results
    connect the vpn
    go back to yoru command window and retype route print.
    post the results.(ommit anything you don't want us to see)

     - Brugh


    Accepted Solution

    Turns out it was only the NIC driver causing this particular issue.  Updated the NIC and all is good. Thanks to all who provided solutions!

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