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5 things that will go wrong with your laptop and how to fix them

Whether the battery has got worse or your laptop is slowing down, we share our tips on how to keep your device in tip-top condition, and what to do when things go wrong.

5 things that will go wrong with your laptop and how to fix them

We’ve surveyed thousands of laptop owners to discover the most common laptop faults. If your laptop’s going to develop a fault, it’s likely to be one of these – so we also tell you how to fix them.

Fortunately, as our survey proves, catastrophic faults that prevent you from using your laptop effectively or at all are rare. Based on our data, we know that laptops are generally pretty reliable pieces of kit; our data suggests most laptops last at least eight years, and the very best brands will, on average, last almost a decade.

But unfortunately that doesn’t mean your laptop will run smoothly up until this point. Below, we’ve listed five trending laptop issues, how you can prevent them, and how you can fix them if it’s already started happening.


We survey thousands of laptop owners so we can reveal to you which laptop brand to buy in 2021.


1. My laptop is slower than it used to be

This accounts for 15% of laptop problems in our survey and is most common problem among laptop owners.

We’ve gone into detail about the mythical reasons why laptops slow down over time (read our guide to slow laptop myths for more), so here we’ll focus on the most likely reasons and how you can prevent them.

Programs and files slowing you down

Over time, as you install more programs and download more stuff, your computer may start to feel the strain, especially if you’re not keeping track of how many programs are running at a time.

We’re big proponents of occasionally refreshing and reinstalling Windows to ensure best performance, and we have guides on speeding up a slow computer and freeing up hard drive space that should help you get started.

Dust in the fans and blocked vents

It might not sound logical, but a dusty laptop is a slow laptop. This is because laptops’ internals produce lots of heat. All that electrical energy being used for loading cat clips on YouTube or, occasionally, getting actual work done, is dissipated as heat, and the fans on your laptop need to spin up to keep the internals cool.

If they can’t stay cool, the laptop protects itself by slowing down how quickly it can do things. A clue that your laptop is slowing down due to overheating would be that it feels much hotter to the touch than it usually does, and that the fans are spinning more noisily than they used to.

To prevent overheating from becoming a bugbear, ensure your laptop always has plenty of space around where the hot air is usually ejected from. Avoid using your laptop directly on top of upholstery, cushions and carpets to prevent built-up of dust and maximise airflow.

Consider whether you might even benefit from an air purifier to keep particularly dusty rooms in check. This isn’t just great for your laptop, but could assist with preventing allergies as well.

Not all air purifiers can remove pollutants from the air. Find out which air purifiers we recommend – see our Best Buy air purifiers.

Man looking pensively at laptop

If you think there’s dust in your laptop already, you could buy a can of compressed air and blow it through the vents. However, this should be done with care as you could simply end up blowing the dust further inside.

If your laptop has screws on the bottom, it’s likely you’ll be able to easily unscrew them and blow the dust out from the inside. Keep in mind that opening your laptop could void its warranty. Although if you’re having dust problems, your laptop may well already be well past its year or two-year coverage anyway.


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2. My laptop’s battery life has deteriorated

This accounts for 14% of laptop problems in our survey. As anybody who’s owned the same smartphone for more than a year will know, batteries simply get worse over time as they chemically age. This process is irreversible and is a part of the lifecycle of a battery.

This ageing starts very gradually, but as batteries get very old they can start to lose huge amounts of charge in a short space of time, or even fail to produce enough power to keep your laptop switched on if it’s doing something particularly demanding.

This is one of the reasons why Apple instigated a controversial performance limit on ageing iPhones; to prevent the phones from asking for more power than a battery could provide at any one time.

You can’t stop a battery from ageing, but you can slow down the process. When you’re not using your laptop, keep it switched off and unplugged when convenient. If there are any battery settings your laptop manufacturer might have added – often they’ll have a setting that keeps the battery below 80% charge to extend its lifespan – keep them switched on.

If you have too many programs running in the background at once, this can drain your battery more quickly. Keep those programs in check to prevent them from gobbling up your precious time away from the mains.

Is your laptop ready for Windows 11? Use our free Windows 11 requirements tool to check.

3. My laptop won’t charge properly

This accounts for 9% of laptop problems in our survey

Charging problems can often stem from a fault with the charging port on a laptop. This is usually caused by either tripping over the charging cable or ham-fistedly plugging it in on a daily basis.

Things can also go wrong in the ‘power brick’ portion of the device, as this is where cables can get a lot of abuse when crumpled up in your bag or being squashed under chair legs. While they seem hardy to start with, a few years of wear and tear can cause damage, and at worst you might even start to see exposed wires.

At that point, or if your charger has failed completely, there are plenty of aftermarket options available if you want to save money. That said, we’d always be tempted to replace it with an identical or recommended model from the laptop’s manufacturer, as you know that it will have been designed with exactly your device in mind.

Charging problems can also stem from a battery fault. We’ve known laptops stored in a cupboard for months to simply refuse to accept a charge. This will manifest itself as the battery charging symbol on your computer showing it’s plugged in, but never actually increasing in percentage. In these cases the computer will usuall switch off as soon as you unplug it.

At this point, it’s worth getting in touch with the manufacturer or a local computer repair shop for help.


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4. I’ve got laptop screen problems

This accounts for 6% of laptop problems in our survey.

Screen problems can appear at any time. Dead pixels are, sadly, a part of life. Although if one comes up early enough, it may be possible to replace under warranty.

Other screen issues include dimming and dark patches. This can be caused by age – the hardware that makes up the screen does age over time and will eventually start to perform less well. However, if you get a dark or light patch suddenly, it could be due to physical damage; either something has hit the screen or perhaps leaked on it.

Whatever the cause, laptop screens are replaceable, and a local computer repair shop should be able to source one that fits your device.

Want a second screen? See our guide to the best computer monitors.

5. Some of my keys on my laptop keyboard stopped working

This accounts for 4% of laptop problems in our survey.

Various things can go wrong with a laptop’s keyboard and general keyboard issues make up a fair proportion of the issues people have with their laptops.

Keyboard keys are extremely simple but also fragile if they get water or crumbs in them.

Many older laptop keyboards can be replaced easily. Usually you’ll see a couple of small indents around the edge of the keyboard that allows it to be lifted out easily.

Although nowadays, most laptops have keyboards that are integral to the device itself, meaning the entire computer has to be disassembled in order to replace it. This also makes individual keys really difficult to remove so it can be an expensive nightmare to get this fiddly and frustrating problem fixed.

Need a new laptop? Our expert tests will help you find the best for your budget – see our laptop reviews.

If it’s solids, such as crumb or sand, you can try using a vacuum cleaner to get the debris out. A toothbrush or other fine wire brush could help as well. Pushing the key down hard a few times can help break up larger objects causing obstructions.

If it’s water damage, you may be out of luck as the electrical button contacts might be permanently damaged. But you should give the computer 24 hours or so to dry out completely before throwing in the towel, metaphorically. We wouldn’t recommend submerging your laptop in rice as this will create more debris to deal with.

While you’re waiting to decide what to do, you can attempt to work around the problem. A simple fix is to buy a very cheap keyboard and use that instead. But if you need it to work right now, you could set up a macro in Word or Google Docs that takes a combination of letters and converts it into another.

For example, if your ‘B’ key isn’t working, you could set things up so that hitting the ‘n’ key next to it three times converts it into a b. Not ideal, but helpful in a pinch.

  • In Google Docs go to Tools, Preferences and then Substitutions to set one up
  • In Word, go to Settings and Proofing to set up auto-corrections.

Our research

In July 2021 we asked 7,374 laptop-owning Which? members about their experiences with their current and previous laptops, including any faults they had and how severe they were.

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