And are you IN CONTROL of all firewalls?
I've lost count of router firewalls that block this and more. Also, this is usually on a LAN since over the internet I no longer support that.
I use my Pc's IP address on my Ipad 2 remote desktop app and it comes up with the same error message every time no matter what combination I try. including using my PC name instead of IP, with or without a port number, and also with and without subnets and gateways. This is for iOS to Windows 10. When I try to connect on my Ipad 2 the message reads "unable to connect to remote pc. please verify remote desktop is enabled, the remote pc is turned on and available on the network, and then try again." please help.

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