When something goes seriously wrong with your laptop, you usually receive an advance warning. A virus might alter your security settings, for example, or a failing hard drive might start making funny noises. If you catch these signals early, you can quickly diagnose and fix your computer.
Many of our recommended solutions involve a thorough malware scan. If you haven't already installed antivirus and antimalware programs on your system, do that now. You can rely on the build-in Windows or macOS programs, or go shopping for another security suite. Just make sure to put in the research: Check out an online buying guide for Windows or macOS, read up on user and professional reviews, and find the right set of tools for your needs. Don't let price deter you—solid computer security is worth the money.
In addition to your primary suite, consider getting a second opinion. You can employ a less-intensive scanner, one that requires you to install fewer files, alongside your main one. Instead of running regular checks, the secondary program would work on an on-demand basis: You only need to fire it up when you need it. We like Microsoft Safety Scanner for Windows and Malwarebytes for macOS.
With so many computer systems out there, problems may manifest differently on each type of machine. But by the time you've finished reading this guide, you should have a much better sense of what various issues look like. And the earlier you spot them, the earlier you can fix them.
1. Sluggish and unresponsive performance
If your laptop begins slowing down, this doesn't necessarily mean it's caught a virus. However, sluggish performance can be a tell-tale sign that a hacker has hijacked your machine for secret activities such as sending spam or mining for cryptocurrencies.
All computers get the occasional error message. It's when you start seeing these alerts regularly, over and over again, that you should start to worry.
Because the culprit could be anything from failing hardware to a virus to a corrupted program installation, you'll need to put in some detective work to discover the root cause of the messages. Start with the text of the error message and any codes it includes. Then go online and type that information into your favorite search engine. You should find some pointers on what's going wrong and how you might be able to fix it.
If your applications start behaving strangely or reconfigure their settings without your permission, your machine has probably caught a virus. After gaining access to your system, malware will often alter your settings for its own purposes, such as preventing you from removing it.
Everyone has to deal with pop-ups while browsing online. But if you're seeing more than normal—and they're pushing suspicious content rather than prodding you to sign up for a newsletter—then you might have a problem. What sort of pop-up content should set off alarm bells? Look out for messages that claim you've won a competition or a reward, flash a malware alert, or nag you to play games, especially if they also make it difficult for you to return to the original page. These can signal that a browser extension is behaving badly or that some kind of malware has taken root on your machine.
As a computer's internal components begin to wear out, it can grow too old to function properly. Refusal to switch on is a sure sign of hardware issues. But you should also keep an ear out for strange and repeated noises coming from the depths of your laptop, because these can indicate that hardware failure is imminent.