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I have a weird issue here.

I'm running Windows 8 Pro. The client computer is also running Windows 8 Pro. Remote Desktop works when I'm in the same network.

I tried connecting using my external IP Address and my DynDNS account, neither works. I disabled Windows Firewall and setup DMZ for my computer on the router, still can't get remote desktop to work.

I verified, port 3389 is open, which is obvious since I'm running DMZ! My ISP, Bell Canada (modem/router: Sagemcom F@st 2864), blocks port 80 and 25, but I don't need those for RDP, do I?

The funny thing is RDP rejects the connection instantaneously for my IP or DynDNS while it takes a while for another address.

Thank you, Michael

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I found the issue.

I am not sure if this is my network configuration or a normal thing but I cannot connect using my external IP when I'm at home, it works fine at another location.

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