I don't recommend C&C based RATs if you want to start one from scratch, because you have to write your own C&C script (you might learn php). even if you willing to use a ready-made one, you MUST customize your rat to be compatible with that script which is pretty much pain in the ass. plus, anyone have your server, can easily inject malicious data in the server you're hosting your C&C Panel
most people using ready-made C&C rats, so they would always recommend newcomers to code a C&C based rats, while they don't realise how time consuming it is.
I would say that C&C based RATs is more suitable for mass infections...
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Have you forwarded 52142 and test it
here and it says opened?