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Generally, we use Process.Start() to launch a exe file in desktop app. But this is not supported in UWP becauses UWP apps are running in the sandbox and it is isolated with the system.
If you want to lanch the cmd.exe from your UWP app, you need make desktop extension by desktop-bridge for UWP app, and call Process.Start() in the desktop extension. For more infomation, you may open your browswer and search for stefan's blog UWP with Desktop Extension – Part 2
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