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8 Warning Signs You Have a Computer Virus

Lisa Belluck  — July 11, 2019

At best, computer viruses are a nuisance. At worst, they can wreak havoc on your important files. While the best course of action is to avoid all viruses, sometimes, one can sneak into your computer–and it won’t always make itself known, at least right away. However, there are several warning signs that your computer might be infected, and the sooner you diagnose the virus, the more likely your computer can be saved. 

Here are 8 warning signs that your computer has been infected by a virus: 

Your Computer Seems Slower than Usual

A slow computer doesn’t always indicate a virus, but if you rule out issues with RAM and hard disk space, it’s certainly possible. Annoying at first, the computer will continue to get slower as the virus uses up more of its resources. If your computer’s opening apps and loading pages at a snail’s pace, run your antivirus ASAP. 

Missing Files

Sometimes, viruses will either delete or encrypt your existing files. This tactic is known as ransomware; a hacker hides your files, and you have to pay the hacker in order to get them back. However, there’s no guarantee he’ll actually return the files after you pay. For this reason, make sure to constantly backup your files and save them to multiple locations. 

New Files

Similar to how it can delete files, a virus is able to add new ones. Often, the new file is simply a replication of the virus itself. If you don’t recognize a file, be on alert, because it might be what’s causing your computer issues. 

Strange Browser Behavior

If you notice your browser has a new home page, it’s likely due to a virus. This virus can also prevent you from closing tabs, and it might disrupt your internet connection. Generally, if you notice your browser acting strangely, it’s a good idea to run your antivirus. 

Pop-Up Windows

If pop-up windows start showing up randomly on your screen, there’s a good chance your computer’s been infected. Pop-up windows aren’t just annoying–they’re also an example of rogueware and scareware. Oftentimes, these pop-ups will pretend to provide help with an existing virus, but if you click on them, you’ll wind up downloading additional malware instead. Always be wary when clicking on pop-ups, especially if they randomly appear when you’re not using your browser. 

Freezing and Crashing

The blue screen of death is a frightening sight, and it signals that your computer isn’t functioning normally. If you see this screen, experience frozen screens, or realize the computer is scrolling, opening apps, or clicking things on its own, all signs point to a virus.

Highjacked Email and Social Media

Have you ever received an email from a friend and wondered whether they’d actually written it? Maybe it was impersonal or didn’t sound like them, or it had typos they wouldn’t usually make? Viruses can spread through email, which makes email a prime target for hackers. Once they log into your account, they can send links to your friends; if those friends click the links, their computers become infected, too. Then, the hacker can send emails from their account to even more friends, infect those friends, send to more friends, etc..

Social Media is also a frequent target for viruses. If a friend posts a strange status or tweets an unfamiliar link, it’s best to contact them right away–their information might be compromised. However, if you contact the account that’s sharing odd links, you’ll likely be communicating with the hacker. Make sure to reach out to your friend via an uncompromised source to ensure they’ll receive your message. 

Additional Security Problems

If you suspect you have a virus, the first thing you’ll probably do is try to install a firewall or antivirus program. However, the virus won’t want to leave, and it will actively stop the program from working. If your antivirus is acting up or missing, you might already have a virus and need a specialist’s help. 

Although there are several ways to identify a virus, the truth is, some of these symptoms are unrelated to viruses. Sometimes, computers have different issues that cause these symptoms; in other cases, viruses are better at hiding, making detection much more difficult. 

In order to best protect your computer, installing and regularly using antivirus software is your safest bet. Don’t wait until you have a virus to look for software, because by then, it might be too late. By installing antivirus software and using smart internet practices, you’re less likely to download a virus–and in the event that you accidentally do, you might even be able to stop it.