A DIF_REGISTER_COINSTALLERS request allows an installer to participate in the registration of device co-installers.

When Sent

Before completing device installation.

Who Handles

Class Co-installer

Can handle

Device Co-installer

Does not handle

Class Installer

Can handle


Installer Input


Supplies a handle to the device information set that contains the device for which co-installers are to be registered.


Supplies a pointer to an SP_DEVINFO_DATA structure that identifies the device in the device information set.

Device Installation Parameters

There are device installation parameters (SP_DEVINSTALL_PARAMS) associated with the DeviceInfoData.

Class Installation Parameters


Installer Output


Installer Return Value

A co-installer can return NO_ERROR, ERROR_DI_POSTPROCESSING_REQUIRED, or a Win32 error code.

If a class installer successfully handles this request and SetupDiCallClassInstaller should subsequently call the default handler, the class installer returns ERROR_DI_DO_DEFAULT.

If the class installer successfully handles this request, including directly calling the default handler, the class installer should return NO_ERROR and SetupDiCallClassInstaller will not subsequently call the default handler again.

Note   The class installer can directly call the default handler, but the class installer should never attempt to supersede the operations of the default handler.

For more information about calling the default handler, see Calling Default DIF Code Handlers.

If the class installer encounters an error, the installer should return an appropriate Win32 error code and SetupDiCallClassInstaller will not subsequently call the default handler.

Default DIF Code Handler


Installer Operation

In response to a DIF_REGISTER_COINSTALLERS request an installer might modify the list of co-installers for the device. For example, an installer might programmatically register or remove a device-specific co-installer for the device that is based on the analysis of the device.

Unless the DI_NOFILECOPY flag is set, an installer that handles this DIF request should copy files that are required for the co-installer(s).

If the DI_NOFILECOPY flag is clear but the DI_NOVCP flag is set, the installer must enqueue any file operations to the supplied file queue but must not commit the queue.

If the installer returns a Win32 error code, Windows stops the installation.

For more information about DIF codes, see Handling DIF Codes.



Supported in Microsoft Windows 2000 and later versions of Windows.


Setupapi.h (include Setupapi.h)

See also




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