How to stop attached USB device / send IRP_MN_REMOVE_DEVICE?

Dag-Erling Smørgrav des at
Wed Aug 15 02:18:04 PDT 2007

Simon 'corecode' Schubert <corecode at> writes:
> Dag-Erling Smørgrav <des at> writes:
> > All modern disks (since at least the early 1990s) automatically park
> > their heads when they lose power.  There is no need to do it in
> > software.
> So it seems that windows is switching off the power of the devices
> when you select "eject".  I can see that some users might feel more
> comfortable with this behaviour.

Yes, if only because it saves power and reduces noise (for USB-attached
mechanical drives at least).  Note that this also requires logic in the
enclosure to cut power to the drive when the device is detached; not all
enclosures do this.  Brand name drives (Maxtor OneTouch, Western Digital
Passport etc.) usually do, while cheap DIY enclosures usually don't.

Dag-Erling Smørgrav - des at

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