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A pop-up says your computer is infected. Here's what to do.

By Luke Liu · Tech Help London · Updated September 2026 · London, Ontario

If a full-screen warning is telling you that your computer is infected, that your files are locked, or that you must call a phone number "before it's too late": it is not real. No genuine Microsoft or Apple warning ever asks you to phone anyone or pay anything. We see this every week in London, Ontario, and it is aimed at older people on purpose. In 2024 Canadians reported $638 million in fraud losses, and people over 60 absorbed about 40 percent of it, according to the Canadian Anti-Fraud Centre.

Do these three things first

  1. Don't call the number, and don't pay. Not by credit card, gift card, bank transfer or Bitcoin. A real company never demands gift cards.
  2. Don't let anyone connect to your computer. If someone is already on the phone with you asking you to install "support software" or read out codes, hang up. It feels rude. Do it anyway.
  3. Close the browser. On Windows, press Ctrl + Shift + Esc, pick your browser, and click End task. On a Mac, press Command + Option + Esc and Force Quit the browser. If nothing works, hold the power button until the machine turns off, then start it again.

When it comes back

If the warning returns when you reopen the browser, don't restore your previous tabs. The pop-up is usually just a web page that reloads itself, not a real infection. Run a scan with Windows Security, which is already on every Windows computer, or the free version of Malwarebytes. Uninstall anything you don't recognise that was installed in the last week.

If you already gave them something

How we help

Our Security clean-up is a fixed price ($119 until December 31, 2026, plus HST). At your kitchen table or remotely while you watch, we remove the pop-ups and any junk software, check what is really installed, lock down your email and banking with two-step sign-in, set up a password manager so you don't need to remember 40 passwords, turn on automatic backups, and leave a one-page safety checklist in plain English. If a pop-up ever comes back, you have a number to call that isn't the one on the screen.

Want a hand with this? We come to your home anywhere in London, or fix it remotely while you watch. Fixed prices you approve first, and if we can't fix it, you don't pay.

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