Re: Can Windows Firewall be Configured to Allow Protocol 47 (GRE)?

From: David Beder [MSFT] (dbeder_at_online.microsoft.com)
Date: 10/21/05

  • Next message: Miha Pihler [MVP]: "Re: how to lock down the SAM database?" 
    Date: Fri, 21 Oct 2005 00:34:09 -0700

    The firewall has a built-in exception for GRE when in the presence of an
    associated PPTP connection.
    If these packets were being dropped they'd show up in the log, but it
    doesn't sound like that's the case. 

    -- 
David
Microsoft Windows Networking
This posting is provided "AS IS" with no warranties, and confers no rights.
"Joe" <Joe@discussions.microsoft.com> wrote in message 
news:23928A0A-7BFB-4EA2-86D1-A3DE682CAF19@microsoft.com...
>I have a windows 2003 server (web edition)
> Using the Add Connection wizard I am allowing incoming VPN connections
> The VPN connection works as expected when firewall is off
> When I turn on the firewall, the client hangs on "verifying username and
> password..."
> From what I understand this means that the TCP port 1723 packets are 
> getting
> through but the GRE packets are not. By turning on firewall logging I can 
> see
> the port 1723 connections open and close so I know the port 1723 
> exceptions
> are working.
> This did work with the firewall on for several days.
> How can I add an exception to the Windows Firewall for GRE?
>
  • Next message: Miha Pihler [MVP]: "Re: how to lock down the SAM database?"

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