Problem Connecting from some computers after NAT-T Enabled

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I have three computers that have been accessing a site using
VPN-Client. The network administrator enabled NAT-T and although a VPN
connection was established, none of the remote computers could be
accessed through the VPN.

Since no one else was having a problem and the vpn profile worked from
other sites, it was assumed there was a problem with the router at my
site.  NAT-T was turned off and the remote computers could be
accessed.  NAT-T was turned on and the problem returned.  One of the
computers was no longer able to connect to the VPN at this point.  The
others connected but could not access remote computers.

A problem with NAT-T was listed for the LinkSys BEFSR81 version 1
router on my side.  I have a DLINK D624M and switched to it.  Now, the
problem is even stranger.

My main computer connects through the router with no problem and I can
access the remote computers. It has a fixed IP.

The second computer is a Toshiba notebook.  It has the same VPN client
and Windows XP Pro as the first but it cannot access the remote
computers even though the VPN connection is made.  It has an IP
assigned by DHCP and is making a wireless connection.  Disabling the
firewall makes no difference.  However, connecting directly through
the cable modem allows the connection to work properly.

The third computer is a Gateway notebook running Vista Ultimate with
the Cisco VPN Beta.  It originally had the same behavior
as the other two computers but now is unable to connect to the VPN
through the router.  It does not seem to see the router and fails

Secure VPN Connection terminated locally by the Client.
Reason 412:  The remote peer is no longer responding.

However, it also will connect to the VPN and remote computers when it
is connected directly via the cable modem.

The router has been upgraded to the latest firmware.  I am not really
sure when the problem went away in the computer which works through
the router since I didn't check each computer as changes were made.

Please help.

Thanks, Sidney

Re: Problem Connecting from some computers after NAT-T Enabled
I am experiencing a very simular issue and was wondering if you manage
to find a resolution to this issue. wrote:
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