If you're running Windows 7 on laptop then you might get an error saying that Consider replacing your battery or There is a problem with your battery, so your computer might shut down suddenly.
You laptop may even automatically shut down even though the battery is fine.
To fix it Open Command Prompt and type the following command :
powercfg -setdcvalueindex SCHEME_CURRENT SUB_BATTERY BATACTIONCRIT 0
Now, even when battery is almost out of power Windows will not shut down automatically. But again, if your battery really runs out then you may find yourself trying to type on a dead laptop.
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