7 Signs Your Computer Has a Virus (And Exactly What To Do Next)

Viruses and malware are sneaky, but they're rarely silent. A computer that's infected — or that's been hijacked by a scam page pretending to be an infection — usually gives you clues. Below are the signs I see most often on customers' machines in West Tennessee, followed by a numbered list of what to do yourself in the next fifteen minutes, and a clear line for when to stop and call.

The signs

1. It got slow all at once

Computers slow down gradually. What's suspicious is a machine that was fine last week and now takes minutes to open a browser — malware running in the background eats the processor and memory you'd normally be using.

2. Pop-ups appear when you're not browsing

Ads or warnings on the desktop with no browser open are adware, and they mean something got installed — often alongside a "free" program or a fake update.

3. Your homepage or search engine changed

If the browser opens to a page you didn't choose, or searches go through an engine you've never heard of, a browser hijacker has changed your settings. More nuisance than danger, but often bundled with worse.

4. Programs open on their own, or the mouse moves by itself

Take this one seriously: it can mean someone has remote access — especially if you recently let a "technician" who called you connect to the computer.

5. Friends get strange emails or messages from you

Either your computer is infected or your email account has been taken over — sometimes both. The fix is a cleanup plus a password change from a clean device.

6. Your antivirus is turned off and won't turn back on

Malware's first job is often to disable the thing that would catch it. Red X marks in Windows Security that won't clear mean assume infection.

7. The full-screen "Your computer is locked — call Microsoft" warning

The most common call I get. A page fills the screen, plays an alarm, shows a Microsoft or Apple logo and a phone number. This is a web page, not a virus. The danger is the phone number: the person who answers will ask for remote access and then for payment. Don't call it. The steps below get rid of it.

What to do right now, in order

1. Don't call any number on the screen, and don't click anything inside the warning — not "Close," not "Cancel," not the X inside the page. Those buttons belong to the scammer.
2. Disconnect from the internet. Turn off Wi-Fi (the network icon near the clock, or the airplane-mode key on a laptop) or unplug the network cable. This stops anything from sending data out or letting someone in while you work.
3. Close the browser the hard way if needed. Press Ctrl + Shift + Esc to open Task Manager, select your browser (Chrome, Edge, Firefox), and click End Task. If the screen is truly locked, hold the power button for ten seconds to shut down, then restart.
4. When you reopen the browser, don't restore the previous pages if it offers. That would bring the scam page straight back.
5. Run a full scan with Windows Security. Click Start, type Windows Security, open it, choose Virus & threat protection, then Scan options, pick Full scan, and let it run — it can take an hour. Let it quarantine or remove whatever it finds. If you have a paid antivirus installed, run its full scan instead.
6. Check your installed programs. Start > Settings > Apps. Sort by install date and look for anything recent you don't recognize — PC "optimizers," toolbars, "driver updaters." Uninstall them.
7. Reset the browser's settings. In Chrome or Edge: Settings > Reset settings. This clears a hijacked homepage and rogue extensions without deleting your bookmarks.
8. Change your passwords — from a different, clean device. Use your phone or another computer. Start with email (it controls password resets for everything else), then banking, then anything with a saved card. If you use the same password in several places, change all of them.
9. Turn on two-step verification for email and banking while you're in there.
10. If money was involved, call your bank. If you paid a scammer, entered card details on a suspicious page, or logged into your bank while someone else had access, call the number on the back of your card today. You can also report it at ic3.gov, the FBI's Internet Crime Complaint Center.
11. Reconnect and watch. Turn Wi-Fi back on and use the computer normally for a day. If the symptoms are gone, you're done. If they return, move to the next section.

When to stop and call

The steps above handle most browser hijacks and light adware. Call instead of continuing if:

• You let someone connect remotely after they called you or after you dialed a pop-up number. Assume they left something behind; it needs a proper cleanup and a check for hidden remote-access tools.
• The scan finds something and it comes back after a restart, or Windows Security won't turn on.
• Files are renamed or won't open and there's a note demanding payment. That's ransomware — don't pay, don't delete anything, disconnect and call.
• Banking or Social Security information may have been exposed and you're not sure what to change.
• The computer is too slow or too locked up to get through the steps.
• You're not comfortable doing it. That's a perfectly good reason. It's what I'm here for.

A $49 remote session covers up to an hour of troubleshooting, which is enough to clear most hijacks, and if I can't fix it you don't pay. If the machine needs a full virus & malware cleanup, that's a flat $79 for one computer including a post-cleanup check, quoted and approved before I start. Active ransomware and business-wide incidents are assessed separately. If the infection has damaged Windows badly enough, a Windows reinstall is $99 with your data backed up first where the drive allows.

Keeping it from happening again: let Windows Update run, keep one real antivirus on (Windows Security is fine for many people; Home Care plans include a managed antivirus I keep current), never install software from a pop-up or search ad, and use different passwords for email and banking — see the online safety guide.

FAQ

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