DllRegisterServer callback function

[Failover Cluster Administrator extension DLLs are available for use in the operating systems specified in the Requirements section. Support for Failover Cluster Administrator extension DLLs was removed in Windows Server 2008.]

The DllRegisterServer function is described in detail in the following topic: DllRegisterServer. The following information applies only to registering Failover Cluster Administrator extension DLLs.


void DllRegisterServer(void);


This callback function has no parameters.

Return value

This callback function does not return a value.


Client-side registration must be done on each computer on which Failover Cluster Administrator runs.

Extension DLLs must be implemented as an in-process (INPROC) server.

For CoCreateInstance to find the correct server, its CLSID must be registered under HKEY_CLASSES_ROOT\CLSID. At the root, an empty-named value must contain the name of the Failover Cluster Administrator extension. Three subkeys are situated below the root:

  • InProcServer32
  • ProgID
  • VersionIndependentProgID

Define an empty-named value in the InProcServer32 key to contain the path to the extension DLL. Also define an empty-named value in the ProgID and VersionIndependentProgID keys to contain the short name of the extension.

To complete the registration, create a key under HKEY_CLASSES_ROOT\CLUADMEX\short name of extension. Define an empty-named value there with the name of the extension. Below that, define a CLSID key with an empty-named value containing the extension CLSID.


Minimum supported client

None supported

Minimum supported server

Windows Server 2003 Enterprise, Windows Server 2003 Datacenter

End of server support

Windows Server 2003 Datacenter, Windows Server 2003 Enterprise