SetupDiCreateDeviceInfo

I have used the functions SetupDiCreateDeviceInfo( ) to add some devices to
the DeviceInfoSet. And the Info is not not belong a pysical device, it's
virtual. I didn't call the function SetupDiDeleteDeviceInfo() to delete the
info then.
I can watch the info in the registry, but cannot del them manunally, How can
I del them?
I write a program to delete them by calling SetupDiDeleteDeviceInfo(), but I
cannot get the info I want to delete as their virtual .

Thanks for any helps!