Everytime I try to play multiplayer the message will pop up and say "Unable to connect to host" whats this mean and how to fix it?

Please specify where you're getting this. What server? Is it a LAN connection?

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On all servers, whenever i click the join button itll say unable to conect to host. Itll do this for every multiplayer option.

Since I have experienced some cases when I do an online play, Windows Firewall would prompt me if I should Unblock the program and add it to the exception list.

It MIGHT be that your firewall is causing this. Add ygopro_vs.exe to the exception lists of your firewall or any anti virus you have.

Also, try running as administrator and see if that helps.

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