7 Signs You Have Malware and How to Get Rid of It

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Once you clear out the crapware from a new PC, it’s like a new house. No creaks and squeaks, no dark corners, everything sparkles. But that pristine state doesn’t last. Before long, you succumb to the hypnotic spinning “wait” icons. In the background, the apps you’ve installed squabble, fighting each other for dominance. In short, it becomes a normal, well-used PC.

Sometimes, though, a slow system or weird behavior can be an outward and visible sign of an inward and serious malware infestation. Is your PC just slow, or is malware dragging it down? How can you know? If you’ve observed any of the seven warning signs below, you may have a malware problem.

Just because you have malware protection installed doesn't mean you can ignore these warning signs. Software isn't perfect, and sometimes, a brand-new zero-day malware attack can slip past your security, at least until the purveyors of your protection push out an update.

1. Pop-Up Ads Pop Up Everywhere

While not as common as before, adware programs bombard their victims with advertisements. Sometimes, they're ads for legitimate products, netting an affiliate fee for the adware perpetrator any time someone clicks on the ad. Other times, they contain links to malicious websites that will attempt to drop more malware on your PC.

Of course, many legitimate websites include various types of ads—they make money selling ad space so you can enjoy their content for free. You can still choose to run ad-blocking software if you really hate those ads. If you start seeing pop-up ads even though you’re running an ad blocker, those ads likely come from an adware program, not from a legitimate source.

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2. Your Browser Keeps Getting Redirected

Not every site redirect is malicious, but if you find that trying to reach DuckDuckGo or Google takes you to an unfamiliar search site, you have a problem. Sometimes, the redirection is less noticeable. For example, a banking Trojan might divert your browser to a fraudulent site that looks just like your bank's real site. In that case, your only clue is the unfamiliar URL in the Address bar.

Redirection attacks often rely on browser extensions, so if you suspect a problem, dig into your browser settings and disable or delete any extensions that you didn't install deliberately. While you’re there, you might as well disable any extensions that you don’t use regularly.

3. An Unknown App Sends Scary Warnings

Creating and distributing fake antivirus programs (also called scareware) is a lucrative business. The perpetrators use drive-by downloads or other sneaky techniques to get the fake antivirus onto your system, then display alarming warnings about made-up security threats.

Scanning for malware with a fake security app is free and super-fast since it's not actually doing anything. But if you naively ask the fake antivirus to fix the problems it found, you’ll find it demands cash on the barrelhead first.

4. Mysterious Posts Appear on Your Social Media

Malware focused on Facebook and other social media sites propagates by generating fake posts or DMs. Typically, these posts include an inflammatory statement, like "OMG were you really that drunk? Look at this picture!" Anyone who falls for the fake and clicks the link becomes the malware's next victim.

5. You Get Ransom Demands

Some malware programs literally hold your PC or data for ransom. Overt ransomware threats encrypt all your pictures and important documents and demand you pay to get them back. Even worse are the ones that encrypt your entire computer, rendering it useless unless you pay to have it unlocked. Others are all bluff and bluster. For example, they may display a warning, purportedly from the FBI or another agency, stating that your computer was used to send spam or view porn, and demanding that you pay a fine before you're allowed to use it again. Of course, even if you do pay, you may not get your documents back. Antivirus apps and security suites should protect against most malware, but you can also double down on safety by adding a dedicated ransomware protection program to your security arsenal.

6. Your System Tools Are Disabled

A smart user, suspecting the presence of malware, might launch Task Manager to investigate or check settings using Registry Editor. If you suddenly find that trying to use these or other system tools triggers a message saying your Administrator has disabled them, it may well be an attempt at self-defense by malware on your system.

7. Everything Seems Perfectly Normal

That's right. Some types of malware do their best to hide all activity, leaving no visible traces. Even when you don't notice anything unusual, it's possible that a bot on your system may be quietly awaiting instruction from its command and control system, perhaps to participate in a DDoS (Distributed Denial of Service) attack. A Remote Access Trojan (or some other form of spyware) may be harvesting your personal information, keeping quiet so you don’t notice. Just because you don’t see it doesn’t mean it isn’t lurking.

So, You've Got Malware. Now What?

If you think malware has taken up residence on your PC, install a powerful antivirus application or security suite immediately. Already have one? Then, apparently, the malware got past its protection—it happens. Manually run an update to make sure your antivirus has the latest malware definitions, and then run a full scan.

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If you still have an unwanted app that your regular security software can't get rid of (or you just want to be doubly sure your system is clean) you can scan your PC again with an aggressive cleanup-only tool such as Malwarebytes Free. Do whatever it takes to get that nasty, malicious program out of your system as soon as possible, before it invites a host of friends to make your security problems even worse.

Once you've dealt with the immediate problem, check your defenses. Make sure that you've installed an antivirus or security suite that gets high marks from PCMag, and that everything is up to date. That should take care of protecting your local data. For another layer of protection, consider installing a virtual private network, or VPN. By running your internet connections through an encrypted channel, the VPN protects your data even in transit. Stay sharp, and keep an eye out for these signs of a malware infestation.