I have an HP Envy 15 notebook PC running Windows 7. I have a 3 TB Western
Digital external hard drive that I use for a backup drive. I do manual backups from
my C: drive to it. I bring up the back-up directory on that hard drive and keep
it minimized until I want to back up a file or directory (or a collection of
those) to it. Frequently, when I click a directory on the backup drive, that
window turns white and my cursor spins, causing an irritating delay in doing the
backup. This must occur to other PC users as well. Do you know what causes that
and what I can do to stop that from occurring?
It’s extremely common. I run into this all the time.
Even better – I’ll bet it only happens “sometimes.”
The problem isn’t really a problem, per se. It’s by design.
And we can’t even blame Windows.
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Many external disk drives will “go to sleep” if they’ve not been accessed in
This power-saving feature actually causes the hard disk to stop spinning, as
that’s the single largest consumer of power in the drive. The circuitry in the
drive stays mostly awake, awaiting a request to actually do something from your
When that request comes in, the circuitry “wakes up” the drive. And like me
before I’ve had my first cup of coffee … it takes a little time to wake
The problem is that the disk needs to “spin up” to full speed – typically
5000 RPM – before the external hard disk can act on whatever it’s been asked to
do. Zero to 5000 take a couple of seconds.
A couple of seconds where your machine is waiting. Depending on the application being used and how it was written, those couple of seconds could cause the program to block completely until the drive is up to speed.
Annoying as that is.
Who’s to blame?
Well, to start with, it’s not a bug – it’s a feature. Drives that do this are
attempting to save power by not spinning the hard disk when it’s not in use.
Unfortunately for many, if not most, this feature is simply built-in.
There’s no way to turn it off.
If you don’t use your drive at all for some period of time, usually around
10 minutes, the drive will go to sleep and turn off its hard disk.
One of the reasons that this can often be confusing is that Windows will
often cache the folder listing for whatever folder is current on that drive. If
you plug in the drive and let it sit for 15 minutes so that it goes to sleep,
you still might be able to see the contents of the top-level folder on the
drive. Windows will have cached it from when the drive was inserted and
doesn’t need the drive to spin up again to read what it already knows.
Do something else, however, like attempt to open a folder or copy a file to
the drive and you’ll be faced with that multi-second delay as the drive wakes
up and comes back up to speed before doing what you asked.
If it’s really a problem, there is a work-around.
Access the drive every so often. If the drive times out at 10 minutes, then
do something to the drive every nine minutes.
A folder read or directory listing won’t be enough, as Windows will have
cached that. Even a file read could be cached.
Nope, you’ll have to do something slightly more serious.
Like write a small file to it every nine minutes. That can’t be cached and
will keep the drive spinning and ready for you when you come along with some
And that’s exactly what NoSleepHD does.
Caveat: I have not tested this utility; it’s just not something that I
need. It appears like a simple solution that you can set up to keep your
external drives from going to sleep.
But of course, as with all tools that you might download from the internet, use it
with caution, and of course, backup early and often.