In this post, you’ll learn more about the Error ERROR_VOLMGR_NO_SUCH_USER – 0xC038002B that is returned when working with the COM-based APIs in Win32
Win32 COM Error
ERROR_VOLMGR_NO_SUCH_USER – 0xC038002B
Win32 COM Error Error Description
The specified notification user does not exist. Failed to unregister user for notifications.