I don't use outlook 2013 so I would imagine you should have a desktop icon to open it. As for mail icon in control panel I'm assuming you mean the mail app in the start page? I log in to my PC using a Microsoft account and the mail app picks this up automatically via the signing in process when logging in to my PC. I don't know how to associate Outlook 2013 with the mail app as it's done via the cloud.
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