Windows Share Dialog Registry Key Locations

This article provides an overview of where Windows stores the registered application handlers for the Share charm and modern Share dialog within the Windows Registry. In modern Windows versions, the sharing mechanism relies on Universal Windows Platform (UWP) and Windows App SDK extension contracts rather than traditional shell context menu keys. Below are the exact registry locations and paths used to identify and populate available share targets.

The Primary Share Target Registry Key

Windows catalogs modern share handlers using the Windows.ShareTarget contract ID. The main registry branch containing registered handlers is located at:

HKEY_CLASSES_ROOT\Extensions\ContractId\Windows.ShareTarget

Because HKEY_CLASSES_ROOT merges per-user and machine-wide settings, the underlying physical registry paths are:

Key Structure and Data Types

Inside the Windows.ShareTarget registry key, handlers are organized by package identifiers:

  1. Package SubKeys:
    Under Windows.ShareTarget\PackageId\, subkeys exist for each registered application package (for example, Mail, Twitter, or OneNote).
  2. ActivatableClassId:
    Each subkey defines the COM/AppX entry point responsible for launching when a user selects that application in the Share UI.
  3. Supported Data Formats:
    Handlers declare the data formats they can accept (such as Text, Uri, Bitmap, or StorageItems) under the DataFormats subkey within their package entry. The Share dialog queries these entries dynamically to show only apps compatible with the shared content type.

AppX Association Registry Locations

Individual modern app registrations are tracked within the AppX package catalog in the registry:

These keys contain the full app manifest configurations, including the windows.shareTarget extension declarations loaded during package deployment.