You may damage your computer.
By pulling the plug or forcing a power-off by holding down the power button, you risk corrupting data on your hard drive and damaging hardware.
I’m not sure what kinds of problems you’re having with the power button, but even that needs to be used correctly, or you could end up with the very problems you’re seeing.
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Use Start to stop
One of the earliest jokes about Windows was the fact that you use the Start menu to stop the computer.
The problem is, it’s no joke.
Turning off or shutting down a computer is not at all like turning off a light bulb, or even a moderately complex piece of electronics.
Turning off a computer is a process. You start the shutdown process using the Start button.
Even though we still refer to it as the “Start” button, Microsoft changed it to have a more generic look after XP. Even so, in Windows 10, if you expand the left-most column of icons in the Start menu (by clicking on the hamburger icon at the top), the familiar word reappears.
The process of shutting down
What happens between clicking on Shut Down and the power going off?
The short answer is: a lot of geeky magic. In fact, a lot of important geeky magic.
Programs are closed, files are saved, information that was kept in memory is written to disk, hardware is turned off in the proper sequence, and more. A lot of important bookkeeping and clean-up work happens as part of the process of shutting down …
… important bookkeeping and cleanup work you want to happen.
Sometimes the power button is OK
Here’s where it gets confusing: sometimes, it’s OK to use the Power button.
On most systems, pressing the Power button briefly is more or less equivalent to using the Start menu to shut down your computer.
What’s important is that you hold it down no longer than one second. If you’re holding it down longer, you’re doing something else, which I’ll talk about next.
But if you press the Power button briefly and see the system begin its process of shutting down, then you’re probably OK to continue to do that.
One caveat: the Power button may shut down your computer properly, or it may put it into hibernate or sleep. Check the Power button settings in the Control Panel to adjust that setting.
Finally, if it shuts down immediately — in the blink of an eye — don’t do that again. That’s the same as pulling the plug, which is bad.
When it’s NOT OK (but you may have to anyway)
If you hold the Power button down for five or 10 seconds until the computer turns off, this is not OK.
That’s like just pulling the power plug.
It completely bypasses the process of shutting down and can result in serious problems. If you shut down your computer this way regularly, stop it because you are almost begging your computer to corrupt the data stored on its hard drive.
The long-hold power-off functionality present in most computers is actually something implemented in hardware, and is meant only as a last resort. In the hardware, it’s almost identical to pulling the plug or removing the battery.
If you find this is the only way you can turn off your computer, something is wrong. The Start menu approach should always work. If it does not — if, for example, your computer never shuts down — that’s a problem that should be resolved, rather than risk data loss every time you force your computer to turn off.
Why unplugging a running computer is bad
When you unplug your desktop computer, remove the battery and power cord from your laptop, or long-hold the Power button to force a computer to stop, you’re taking action outside of the operating system’s control. I was tempted to say “outside of Windows’ control”, but this applies no matter what operating system you’re running.
Even when you’re doing nothing with your computer, it’s always doing something. In fact, it’s often doing quite a lot.
Files are open, programs are running, the disk may be being accessed, and more might be happening. It’s almost impossible to predict exactly what is running, and therein lies the problem.
Let’s say a program is updating something on disk. It doesn’t have to be something you’re doing; it could be some other program, like your anti-malware tools, system indexing tools, or something else running on your machine. If you suddenly remove the power in the middle of that operation, any of the following may happen:
- Nothing. You got lucky and the writing actually completed, because it’s so darned quick. This is probably the most common case, but it leads to a false sense of safety.
- The file that was being written is incomplete. Depending on the program writing the file, this can be completely benign, or show up as a major problem the next time that program tries to access that file.
- The file system directory entry that locates that file on disk could be incorrectly or partially updated, if that’s what the computer was writing when you pulled the plug. This can be benign, but in the extreme case, it can actually render the file system corrupt and you can lose not only the file that was being written, but large numbers of other files on the disk. This is bad: very bad.
- The disk drive could be interrupted in the middle of writing a sector of information to the hard disk media. That could result in CRC errors for that sector and nearby information in other files. This may require a CHKDSK /R to repair, or, in the worst case, more advanced disk recovery and maintenance. Fortunately, with modern drives, this is rare.
Hopefully, by now you get the idea: just pulling the plug or forcing a shutdown is a bad idea, and should be used only as a last resort, immediately prior to resolving the underlying problem that required it.
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