windows VPN Error 800

I have a senior’s exec laptop who he can’t VPN with to the network from his home. another PC at his home is able to VPN in fine using the same router. the laptop’s windows firewall is off, it has no other firewall software, it has Norton Corporate edition which doesn’t have a built in firewall, i even disabled the the auto protect, and tried no go. i changed the router’s ( WRT54G) MTU settings to match exactly the MTU settings of the DSL modem and still no go,checked VPN pass thru and is enabled on the router, it always get stuck on “connection to *.*.*.* ” . the last thing i did i sby pass the router and connect directly thru the DSl modem still no Vpn connection.

any help on this is much appreciated.