"app://" - URI scheme, tells the OS how to handle the request (app launcher).
"80C...891" - App's ProductID GUID. Unique for every app (but does not change on updates). Identifies the app in question.
"/_default" - Use the app's normal launch task (as opposed to a launch task for a live tile or something).
"#" - URI fragment indicator, specifies where within the app to navigate to.
"Microsoft.Mcx.Mobile.UpdaterShell" - Name of the assembly containing the desired XAML file (the specification method is WP standard for embedded resources).
";" - Separator between the assembly and the path within the assembly; standard in WP.
"component/Views/" - Path to the embedded XAML view that you want to open (also WP standard format for embedded resources).
"AdminView.xaml" - the name of the (embedded) XAML file that you want to open.
Do not private message me with questions that should have been posted on the forum! Not only are you wasting your time - I'm not going to bother writing an answer to such a question for only one person - but I will probably block you from PMing me in the future as well.
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