WARNING: Since you are using --dev tun with a point-to-point topology, the second argument to --ifconfig must be an IP address. You are using something (255.255.255.0) that looks more like a netmask. (silence this warning with --ifconfig-nowarn)
this warning says it pretty much: something seems wrong with your client config file; compare the client config file to the working one on XP. Posting your server and client config files will also help :mrgreen:
