A pop-up says your computer has a virus? Don’t call the number!

A webpage suddenly fills the screen. It flashes, makes a noise or announces that your computer has been infected. There is a telephone number to call immediately.

Stop. This is a common technical-support scam.

Genuine Microsoft error and warning messages do not include telephone numbers. The message is designed to frighten you into calling a scammer, giving them payment details or allowing remote access to your computer.

What to do

  1. Do not call the number.
  2. Do not click the warning or download anything.
  3. Close the browser. On Windows, try Alt + F4. On a Mac, try Command + Q.
  4. If the browser refuses to close, restart the computer.
  5. When reopening the browser, do not restore the suspicious page if it is offered.

Seeing the pop-up does not, by itself, prove that your computer has a virus.

If you called or gave someone access

Disconnect the computer from the internet and seek help from someone you trust. Change any passwords you revealed, preferably using a different trusted device. If you supplied card or banking information, contact your bank immediately.