How to know if my device has a virus?

“Computer virus” is often used as an umbrella term for all the different types of malware. But how can you know if your device has malware? Without antivirus software, most of the time you can’t tell for sure. Read more on what to look for and how to know if your device has a virus.

What to look for in Mac and Windows computers

A common myth is that malware is only a problem for computers running on Windows operating system. While it’s less common, Macs can be affected as well. You can look for these symptoms on both.

  • Programs or internet slow down
  • Excessive freezing and crashing
  • Emergence of unknown ads, popups or files
  • Browser changing the home page, unknown toolbars
  • Unknown sent messages or emails
  • Windows appearing and vanishing immediately

Unfortunately, these signs aren’t always a clear indication of infection. There are many other possible reasons for your computer acting up. Sort of like a headache can be a sign of sickness, dehydration, muscle tension etc.

Mobile devices aren’t safe either

Web criminals are where the users are. While traditional computer viruses aren’t a threat to mobile devices, other kinds of malware are. As with computers, signs of infection can be ambiguous on mobile devices too. Be on your guard if you encounter these symptoms.

  • Strange and unwanted apps
  • Data drain
  • Apps or operating system crashes
  • Ads popping up
  • Odd charges in your phone or credit card bill
  • Bank authentication suspiciously slow

Even though it’s rare, it is possible for an iOS device to have malware in it. Especially if you download apps from unofficial appstores.

Humans can’t detect all malware

Most of the time humans can’t detect malware. Many possible warning signs can just as well be something else. Luckily, we don’t have to. There is software that will do it for us. You can use for example F‑Secure’s Online Scanner to remove malware from your PC completely free!


Watch our expert explain how to know if your device has a virus

F‑Secure SAFE got you covered

F‑Secure’s award-winning SAFE protects you from all malware. Not only that, it has other useful features like browsing and banking protection and a lot more. You can get it both on your computer and mobile devices to keep you safe. There’s no need to be unsure if your device has a virus, F‑Secure will detect them for you.


Try F‑Secure SAFE internet security for free

  • Free trial for 30 days and 3 devices
  • The trial period does not obligate you to buy the product
  • Using the product for the trial period does not require you to provide any credit card or banking details

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