How to block internet connection if VPN server disconects?

[KoolChamp]

Hi there guys!

SoftEtherVPN is really a wonderful tool.
I use it to bypass an IP-Ban on one site.

But I have a little problem.
Sometimes connection to VPN server is lost.
Immediately after this - a site see my real IP, blocking me, delete my account, and ban the whole VPN IP.
So I have to change a server and start with new account from the beginning.
Really annoying.
I google the problem but still not found a solution.
I wonder if there is a way to stop my whole internet connection in case of VPN disconects?
Please advice me how to do it.

Best regards,
Master K.

[KoolChamp]

Sorry I forgot to mention that I am using windows 7.

[thisjun]

Please delete physical existing default gateway after connecting VPN.