IOCTL_MOUNTMGR_CHECK_UNPROCESSED_VOLUMES - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers
#ifndef _NTIOAPI_H

#define IOCTL_MOUNTMGR_CHECK_UNPROCESSED_VOLUMES    CTL_CODE(MOUNTMGRCONTROLTYPE, 10, METHOD_BUFFERED, FILE_READ_ACCESS)

#endif

View code on GitHub

This IOCTL is documented in Windows Driver Kit.