VPN Into Home Network over Wireless

Hello,

I am trying to VPN into my network via wireless.

EXTERNAL CLIENT >> MN 500 >> ISA SERVER >> HOME NETWORK

I am able to VPN when I remove the MN 500 from the picture (i.e. direct
cable connection to the Server). I am also able to VPN "out" from my home
network to work. However I am unable to VPN via wireless into my home
network. The connection is established but gets stuck at 'verifying username
and password". When I check the logs on my ISA 2004/Win2K3 server it says
that GRE packets are not getting through (see complete event log below).

Any help as far as if this is possible and if so how, would be much
appreciated!

Thanks,
Stephen



Event Type: Warning
Event Source: Rasman
Event Category: None
Event ID: 20209
Date: 6/11/2005
Time: 10:00:44 PM

Description:
A connection between the VPN server and the VPN client has been established,
but the VPN connection cannot be completed. The most common cause for this
is that a firewall or router between the VPN server and the VPN client is
not configured to allow Generic Routing Encapsulation (GRE) packets
(protocol 47). Verify that the firewalls and routers between your VPN server
and the Internet allow GRE packets. Make sure the firewalls and routers on
the user's network are also configured to allow GRE packets. If the problem
persists, have the user contact the Internet service provider (ISP) to
determine whether the ISP might be blocking GRE packets.