O Github para Windows é um o instalador do ClickOnce e, como um usuário você não pode controlar a pasta de destino do instalador ClickOnce. Em vez disso, eles sempre serão instalados no "cache de aplicativos do ClickOnce", que é %USERPROFILE%\AppData\Local\Apps.0
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ClickOnce applications are always installed in the Apps subdirectory of local application data.
ClickOnce Deployment will install an application in the user Application Cache per user (not in X:\Programe files\folder) and will be managed by the ClickOnce service. There is no way you can install it to another folder directly using ClickOnce. This means you cannot change the ClickOnce installation location.
Nope. You can't. One of the design goals of ClickOnce applications is that they require no administrative privileges, and the only places you can write with impunity on Vista and Windows Fabulous (7) are under the user's profile.
The philosophy behind ClickOnce is a bit different to normal programs installed in "C:\Program Files". By installing the application in the user's directory, the application can be installed without having admin rights and the automatic updating system can work without having any awful security issues.