Hi!
Well, although it's impossible to make entire server ignore remote requests, you can relatively easily
make your application listen to only local requests.
You can use software firewalls to lock down all inbound ports. Alternatively, you could also uninstall UltiDev Cassini Explorer to prevent it from listening on port 7756. If there are no other applications, then you are pretty much locked down.
Please let us know if this was helpful.
Best regards,
UltiDev Team.
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