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I want to block a certain IP address at my firewall which is connected to my PC, but I don't know what it looks like.

Is there any way I can see a list of all IPs having connections with my PC?

So far I tried netstat -b -n in the command line, but from the list I get the only one showing appears to be the IP of a server that I don't want to block.

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Yes, there is. A command-line approach to this is using netstat. See this how-to.

netstat is very similar to using netstat on Unix-based systems, by the way, so this applies not only for Windows.

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thanks. And to block the IP I use the hosts file, right? – Alex Sep 14 '12 at 23:06
@Alex For blocking IPs you use a firewall. Host files are about resolving named addresses. – gertvdijk Sep 14 '12 at 23:10
ok i found out this thing:… – Alex Sep 14 '12 at 23:25
@Alex by default windows 7 firewall blocks all unsolicited attempts to connect to you PC, unless the ip is requested to make a connection from your end, this could be done a legitimate program or malware doing this. Exceptions can be made in the windows firewall program itself, you might see what exceptions are there. – Moab Sep 14 '12 at 23:36
well, here's the full story:… :( – Alex Sep 14 '12 at 23:38

So I found out after all his IPs. Some guy HostBot from USEast posted this link.

Here's how to do it:

  • start => cmd
  • type "mmc"
  • file => add/remove snap-in
  • select from the left "ip security policy manager", add it to the right and type ok
  • now from the console root, right click "ip security..." and select "Create ip security policy", next, next, finish
  • click "add" in the edit screen of your policy, and in the "ip filter lists" screen add a new filter.
  • add new IPs to the list; leave the Source address as "any Ip address" and the destination must be "a specific Ip address or submask", where u enter each of the following:
    • click ok, save all settings, then right click policy => assign...
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Those addresses in the link are not /16. They are /32. a /16 is over 65,000 addresses – Sirex Sep 18 '12 at 0:07

This is actually true for those who reading this and shaking your head in disbelief this is going on. I don't believe there is anyway to block his IP (the reason is the user is not connecting to your computer but the computer), but here is the teamliquid thread on it going on. According to them the only work around is this (edited for language)

To Play user map setting, make game name as desired but change gametype to Top vs bottom. Once your lobby is full.

Remake same game name with the password as "1" The reason is frux is just affecting the UMS (Use map settings) lobby list. A lobby list is just needed a name to bring them together.

For example: you wish to host lobby for sunken d. You would make the game name "Sunken D!!!" select the map but change setting in game creator to Top vs Bottom. Now your game name is able to be joined. When your lobby is full, remake the same game name as before "Sunken D!!" just add a password you notify to use that in the lobby before you remake the game

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