Registering Application Dependency (Windows Media Player SDK)

Applications that use APIs provided by the Windows Media Player SDK or Windows Media Format SDK are dependent upon the runtime components of those technologies. You can register your application as being dependent on those components as part of your application setup.

When you register your application, you can choose one of two levels of dependency: blocking or dependent. When one or more application is registered with a blocking dependency on one of the runtime components, the component will be blocked from a rollback to a previous version. Dependent applications that are not registered as blocking do not block rollback. Instead, before the rollback is performed, the user is displayed a message stating that applications are dependent on the component.

To register your application, you must set a value in the registry that identifies your application. The registry value to set depends on the component on which your application is dependent. You can also set two additional values per dependency to provide extra information about your application.

The following registry values are used to register dependence on Windows Media Player SDK runtime:

  • HKEY_CLASSES_ROOT\Software\Microsoft\MediaPlayer\Setup\ REF_TYPE \App, "APP", "APP_STRING"
  • HKEY_CLASSES_ROOT\Software\Microsoft\MediaPlayer\Setup\ REF_TYPE \Descriptor, "APP", "REF_DESCRIPTOR"
  • HKEY_CLASSES_ROOT\Software\Microsoft\MediaPlayer\Setup\ REF_TYPE \Version, "APP", "WMP_VERSION"

The following registry values are used to register dependence on the Windows Media Format SDK runtime:

  • HKEY_CLASSES_ROOT\Software\Microsoft\WindowsMedia\Setup\ REF_TYPE \App, "APP", "APP_STRING"
  • HKEY_CLASSES_ROOT\Software\Microsoft\WindowsMedia\Setup\ REF_TYPE \Descriptor, "APP", "REF_DESCRIPTOR"
  • HKEY_CLASSES_ROOT\Software\Microsoft\WindowsMedia\Setup\ REF_TYPE \Version, "APP", "WMF_VERSION"

The following variables are used in the registry values listed above:


Replace with BlockingRefCounts for blocking dependency, or with DependentRefCounts for non-blocking dependency.


Name or short descriptor of your application. This string will not be used in messages displayed for the user. This value is the identifier used in all three registry values associated with each of the runtime components.


Descriptor of your application. This string may be used in messages displayed for the user.


Description of how your application uses the component. This value can include a maximum of 256 characters.


Version of Windows Media Player required by your application. If no version is specified, the default value is assumed to be


Version of the Windows Media Format SDK required by your application.

The following three example registry values demonstrate how to configure the values for your application:

  • HKEY_CLASSES_ROOT\Software\Microsoft\MediaPlayer\Setup\DependentRefCounts\App, "SouthridgeVideo", "Southridge Video Player"
  • HKEY_CLASSES_ROOT\Software\Microsoft\MediaPlayer\Setup\DependentRefCounts\Descriptor, "SouthridgeVideo", "Southridge Video Player uses the Windows Media Format SDK to play video files."
  • HKEY_CLASSES_ROOT\Software\Microsoft\MediaPlayer\Setup\DependentRefCounts\Version, "SouthridgeVideo", ""

Registry Settings