Re: router filters
Try blocking port 80 (http), for outbound traffic. Also, you may want to make sure the IP address to the computer you are trying to filter is correct. If it's setup DHCP, if you turn the computer off, and the address was 192.168.1.100, and turn it back on, it may get a different address, therefore letting it online. You may be able to work around this by setting up a static IP address for each computer.
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