This IOCTL allows a client to simulate a Plug and Play device interface arrival notification with the given volume name. If a client does not register a device interface of type MOUNTDEV_MOUNTED_DEVICE_GUID, the mount manager is not alerted of its arrival. However, the client can alert the mount manager of its volume's arrival directly by means of this IOCTL.

This IOCTL allows clients to obtain drive letters for newly created volumes during text mode setup when the Plug and Play device installer is not running.

Clients that have registered a device interface of type MOUNTDEV_MOUNTED_DEVICE_GUID in the normal way should not use this IOCTL.

Major code


Input buffer

The mount manager client loads the following structure with the nonpersistent target device name. The initialized structure, MOUNTMGR_TARGET_NAME is inserted at the beginning of the buffer at Irp->AssociatedIrp.SystemBuffer.

Input buffer length

Parameters.DeviceIoControl.InputBufferLength in the I/O stack location of the IRP indicates the size, in bytes, of the input buffer, which must be greater than or equal to sizeof(MOUNTMGR_TARGET_NAME).

Output buffer


Output buffer length


Input / Output buffer


Input / Output buffer length


Status block

If the operation is successful, the Status field is set to STATUS_SUCCESS.

The input buffer size, indicated by InputBufferLength, must be large enough to hold the structure MOUNTMGR_TARGET_NAME and the symbolic link name that follows it. If it is not large enough, the Status field is set to STATUS_INVALID_PARAMETER.


For more information, see Supporting Mount Manager Requests in a Storage Class Driver.


Requirement Value
Header mountmgr.h (include Mountmgr.h)

See also