How To Block ALL PORTS

I need some code that illustrates how to block all ports for a computer such that no (Zero) internet activity can occur. ( and then be able to turn them back on again, just like a Firewall blocking all ports).

Who is Participating?
A hook on the TCP/IP stack calls? Just wondering...
Perhaps you could start here or with the Windows DDK
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TheRealLokiSenior DeveloperCommented:
if it's a lan connection, you could simply clear your gateway, so data can not route
(route delete
and reset it after to your lan gateway
route add -p mask (if .1 is your router/gateway)
quantum2Author Commented:
Hey Sftweng,
thanks for the links. This will help a great deal. If you are interested, I will give you 300 more points if you take the Winsockfirewall code and create an sample application that has the following.

one form, two buttons.

Button 1 - Block all traffic
Button 2 - Enable traffic

Thats it.

While I havent looked at this code in great detail, it would appear that this is as simple as assigning a IP range rule from to

I got slammed at work and dont have time to weed through all of this, so if you are interested in creating a sample that uses their code and any libraries, all I would need is the units necessary to make the sample work as well as any components they are dependant on and the above listed functionality.

Thanks for the help

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