In order to enable Multi Factor Authentication, log on the Archiver with the user you want to enable MFA on and go to the user profile settings.
Go to the Two Factor Authentication section.
Click on the Enable OTP button.
Scan the QR code with an app like Google Authenticator, generate an OTP code and insert it to confirm and activate 2FA. You can also use the secret token.
After confirmed, the MFA will be enabled.