Scan the QR code shown on your PC. Now, whenever extra verification is needed, you’ll receive a prompt or a one-time code from Authenticator.

Instantly, the Configure mobile app screen will appear on your PC screen, displaying a QR code. You will need to scan this code with the authenticator app. Now, open the Microsoft Authenticator ...

One scam app even captures your QR codes. You don’t have to look very hard for it: The developer took out an App Store ad, which means it is prominently shown when you search for authenticator apps.