Workaround for VPN not accessing HTTPS Web site properly

The former suddenly found in foreign countries to assume that the VPN at home can not access the HTTPS site, check the route what are normal, hence the suspicion is the community broadband firewall, nothing.

This evening and carefully analyzed the next, will not be the previous changes in the wireless router reason? Nat has also been encountered before the failure to open the VPN can not connect the problem, so landing to the router management platform, found that there is a forwarding rules column, enter, open "Special application", has the following text hint:

Some programs require more than one connection, such as Internet games, video conferencing, and internet telephony. Because of the presence of firewalls, these programs cannot work under simple NAT routing. Special applications enable some of these applications to work under NAT routing.

It seems to be a big problem. Add an entry:

Id	Trigger Port	Trigger protocol	Open ports	Open Agreement	State	Edit
1	1723	All	1723	All	Effect

1723 of these are the ports that the PPTP protocol will use.

Disconnect the computer network and reconnect to find the problem resolved.

Later restarted the computer, found again, 捯 onto for half a day, the original is the router MTU number of problems, changed to 1490, restart the route, fix.