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While using the Duo two-factor authentication mobile app is the best and recommended authentication option, it is also recommended that users generate and safely store a list of backup single-use codes that can be used when:
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you do not have immediate access to your previously registered device
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if you change devices or phone numbers
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your device is not working
These backup codes can be entered in lieu of your other, regular authentication method.
Follow the instructions below to generate new single use codes. These instructions apply when using a mobile device for two-factor authentication.
Step-by-step guide
Navigate to the IST 2 factor authentication (2FA) website: https://uwaterloo.ca/2fa (right-click to open page in a new tab, if desired)
Under Select a second factor tool and manage your devices, click "add a device or manage an existing device" and log in
If Duo automatically attempts to send a push to your mobile device, click "Cancel" at the bottom of the screen
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5. This will text a set of single-use codes to your mobile device
6. These steps may be repeated when you have used all previous codes
Important notes
Record this list of single-use codes and keep it somewhere safe but available to you
Only use a code when your primary device and method of authenticating are not available to you
Codes will remain valid for one year, after which they will expire and new codes will be required. These steps may be repeated when you have used all previous codes
In early April, a feature will be enabled that will send an email notification to the requestor's on-campus email address to inform/verify the code request
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