Just buy a decent router with a good firewall.
Then install Sygate SPF. Try it. It might work.
If it works, do this: https://www.securityfocus.com/bid/6684/solution
Then avoid the internet.
For comparison, when using my XP system I typically run with a wireless-only network with wireless always switched OFF unless I am specifically downloading something onto that XP system.Then it is virustotal to scan and a bit of brainwork to be sure I am safe. Sygate SPF and the router hold the line against attack whilst I am networked. Immediately the task is complete, the network is switched off.
I sometimes game on this machine with my family, Quake variations, Total war and Colonial conquest. The internet is disabled on the specific router we use to extend the internet to a particular room and we are safe to play.
Basically if you are running ReactOS, (and you shouldn't be) then treat it and all apps as being unsupported and use your best judgement as to what to do, just the same as if you were running XP (and you shouldn't be) .
Testing a firewall on ReactOS at this stage should just be to see if it works certainly not to see if it protects you during real usage with ROS as your OS. IF you are doing the latter then the advice about engaging the brain is the real advice you need at this point.
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