Whats this ?

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Curr entVersion\Shell
Extensions\Approved]
"{A4D78B20-6E05-1069-8758-08002B2BD64F}"="Sample Drag&Drop Extension"

Is it needed ?

Can someone explain I have not seen any documentation on it. It was in an
SDK example 'DropExt' the example does not seem to work or do anything.

Aaron