Signs Your Computer May Have Malware

If your computer has been acting strange lately — running slower, showing pop-ups you didn't ask for, or just feeling "off" — you may be looking for the signs of malware on your computer. Malware means harmful software: a program that gets onto your computer without your permission and causes problems, from annoying ads to stolen passwords.

The good news is that malware usually leaves clues. You don't need to be a computer expert to notice them. This article walks through what to watch for on a Windows PC or a Mac, how to check your own computer in a few minutes, and what to do if you find something wrong.

You don't have to figure this out alone, and you don't have to panic. Calm, steady steps are enough.

The warning signs to watch for

Any one of these by itself might have an innocent explanation. Several of them together are worth taking seriously.

1. Your computer runs much slower than usual — programs take longer to open, and the whole computer feels sluggish even right after starting it up.
2. Pop-up ads appear even when you're not in your web browser — this is different from a pop-up on a website; it means something is running in the background.
3. Your browser's homepage or search engine changed on its own, or you keep getting sent to websites you didn't choose.
4. New toolbars, icons, or programs appear that you don't remember installing.
5. Your antivirus program is turned off, and you're sure you didn't turn it off yourself.
6. Friends or family say they got a strange email or message from you that you never sent.
7. Programs freeze, crash, or restart on their own more than they used to.
8. Your computer's fan runs loudly even when you're not doing much, which can mean something is working hard in the background without your knowledge.

How malware usually gets in

Knowing how malware arrives can help you avoid it next time. The most common paths are clicking a pop-up that claims your computer needs an "urgent update," downloading a program from a website you don't fully trust, opening an attachment in an email you weren't expecting, or clicking a link in a text or email that leads to a fake site. None of these require anything unusual on your part — they're built to look ordinary, which is exactly why they work.

This is also why malware can slip in even on a computer that's otherwise well cared for. It isn't a sign you did something wrong; it's a sign the people behind it are getting better at disguising their tricks.

How to check your Windows computer

Windows has a built-in tool called Task Manager that shows everything running on your computer.

1. Press Ctrl, Shift, and Esc at the same time to open Task Manager.
2. Look at the Processes tab for anything using a lot of your computer's power that you don't recognize.
3. Click the Startup apps tab (or go to Settings > Apps > Startup) to see what opens automatically when your computer turns on. If you see a program you've never heard of, that's worth a closer look.

You don't need to remove anything yourself right now — this step is just about noticing what's there.

How to check your Mac

A Mac has a similar built-in tool called Activity Monitor.

1. Open Spotlight (the small magnifying glass near the top right of your screen), type "Activity Monitor," and open it. Or go to Applications, then Utilities, then Activity Monitor.
2. Look through the list of what's running. Click the % CPU column to sort by what's using the most power, and see if anything unfamiliar is near the top.
3. Open your Applications folder and scan for any program you don't remember installing.

What to do if you spot these signs

Finding a warning sign doesn't mean your computer is beyond help. Take these steps calmly, in order:

1. Don't enter any passwords or account numbers on that computer until you've checked it further.
2. Run a full scan with a trusted antivirus program. Let it finish completely, even if it takes a while.
3. If the scan finds something, follow its instructions to remove it, then restart your computer.
4. Change your important passwords — email and banking first — from a different, trusted device if you can, in case the first one was already compromised.
5. Keep an eye on your bank and credit card statements for a few weeks afterward.

What to do if you're stuck

If this feels like more than you want to handle alone, that's completely reasonable. If something already feels wrong, or you'd rather a person handle it, we can help in your home or remotely. Call (916) 521-0065.

A quieter way to avoid this altogether

Checking Task Manager or Activity Monitor is a good habit, but it's easier to prevent malware than to clean it up after the fact. If you want quiet protection on your Windows or Mac computer — with a real Porchswing person to call — learn about PorchswingProtect. Or call us at (916) 521-0065 and we'll help you set it up.

Common questions

Can my iPhone or iPad get malware the same way?

PorchswingProtect is built for Windows and Mac computers, not phones or tablets. Phones face different risks, mostly from scam links and fake apps rather than the kind of malware described here, so the steps in this article are for computers.

Will restarting my computer get rid of malware?

Usually not. Restarting can close a program that's misbehaving for the moment, but most malware starts right back up again. A real antivirus scan is what actually finds and removes it.

Is free antivirus good enough?

Free antivirus can catch many threats, but it usually won't call you back if something goes wrong or walk you through a confusing alert. That's the gap PorchswingProtect is built to fill — the same kind of protection, plus a real person on the other end of the phone.