VPN Connection

I'm trying to establish a vpn connection from my laptop to my network. The setup that I currently have is:

Laptop [L] ----- NAT Device (presumably with a firewall [R1]) ----- Internet ----- NAT Server (ISA server with vpn enabled [R2]) ----- Internal Network (inc. Domain controller [DC])

I have no control over R1 and full control over R2 and the internal network. I have rules setup to allow any communication from internal, localhost, and vpn clients to internal, localhost, and vpn clients.



When trying to connect it connects fine but seems to timeout when authenticating. I also noticed this in the firewall log. It only shows up if I connect from outside my

network. If I try to connect from inside it works fine and does not give these logs.

Time IP Protocol Source Destination Source Network Dest Action Result Protocol
17:20:28 UDP 192.168.87.15:137 192.168.87.1:137 Local Host Internal Denied 0xc0040030 NetBios Name Service
17:20:28 UDP 192.168.87.15:137 192.168.87.1:137 Local Host Internal Denied 0xc0040030 NetBios Name Service
17:20:32 UDP 192.168.87.15:137 192.168.87.1:137 Local Host Internal Denied 0xc0040030 NetBios Name Service
17:20:36 UDP 192.168.87.15:137 192.168.87.1:137 Local Host Internal Denied 0xc0040030 NetBios Name Service
17:20:36 UDP 192.168.87.15:137 192.168.87.1:137 Local Host Internal Denied 0xc0040030 NetBios Name Service

Click to expand...

192.168.87.15 is the address assigned to the VPN Client, 192.168.87.1 is the address for the DC. Does anyone have any idea as to why I am getting these denied requests? I am currently using PPTP, and will try L2TP tomorrow to see if that works.