I'm trying to build a voip app that is used by outlook as it's click to dial. I'm trying to figure out how to make the default choose my app, but because it's not in the app store yet, I can't choose it from the windows GUI. I think I have to play around with the .regedit but I can't even get a simple calculator to open up when I try click to dial on anything on the system.
Computer\HKEY_CURRENT_USER\SOFTWARE\Classes\tel\shell\open\command
@="\"calc" \"%1\""
You also need to make sure it is marked as a protocol with
That should make tel: work. If there is already another handler installed for tel: on your machine then this will not make you the default.
To allow users to set your handler as the default in the settings app you need to register your application with "Default Programs".