Is a pop-up warning saying my computer is infected and I must call a number a scam?
Yes. These are tech support scam pop-ups. No legitimate antivirus or operating system company sends browser pop-ups telling you to call a phone number.
Last reviewed: 10 June 2026
Explanation
Tech support pop-ups are designed to look like official Microsoft, Apple, or antivirus warnings. They often freeze your browser, play a loud alarm sound, and display a toll-free number to call. The pop-up cannot actually be closed by clicking the X, which adds to the panic.
If you call the number, a convincing 'technician' answers and asks to take remote control of your computer using legitimate tools like AnyDesk or TeamViewer. Once connected, they show you normal system logs and pretend these are signs of infection to justify charging hundreds of dollars for fake 'removal' services or unnecessary software subscriptions. Some also install real malware or steal files while connected.
Microsoft, Apple, and legitimate security companies do not reach out to consumers via browser pop-ups asking them to call a number. If your computer has a real problem, your installed antivirus software will notify you through its own application interface, not through a browser window.
To close a frozen pop-up, press Alt+F4 on Windows or Command+W on Mac. If that does not work, force-quit the browser entirely. Run a scan with your real antivirus software afterward to confirm nothing malicious was installed from the page.
Common red flags
- Browser freezes and cannot be closed normally
- Loud alarm or robotic voice claiming your computer is compromised
- A phone number to call for 'immediate support'
- Mimics the logo and colour scheme of Microsoft, Apple, or a known security brand
- Claims to be from your ISP or government saying illegal activity was detected
- Urgency language such as 'do not shut down your computer'
What to do now
- Do not call the number on the pop-up under any circumstances
- Force-close the browser: Alt+F4 on Windows, Command+Q on Mac, or use Task Manager
- Run a full scan with your genuine, installed antivirus software
- Clear your browser's cache and check for any unwanted browser extensions
- If you already gave remote access, disconnect from the internet immediately and run a security scan
- If you paid by card, contact your bank to dispute the charge
Frequently asked questions
What if I already gave the caller remote access but did not pay?
Assume the worst. Change all passwords immediately, especially for email and banking. Scan your computer with legitimate security software, and consider taking it to a trusted local technician for a full review.
Why can I not close the pop-up normally?
Fraudulent pages use JavaScript code that prevents the browser's normal close behaviour. Force-quitting the browser bypasses this entirely.
Is the pop-up itself a virus?
Usually not — it is a web page designed to look alarming. However, some pop-up pages attempt to download actual malware, so running a scan after encountering one is always advisable.