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If you have replaced your phone/device or reset the device, contact the IT Help Desk to reset your authenticator
Before you begin – check the SETTINGS on your mobile device, Microsoft Authenticator will need to access to the camera
On iOS, go to Settings-Authenticator-turn on camera
Allowing Face ID is optional
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Next, using an Internet Browser, go to https://mysignins.microsoft.com using the iphone
Click on Add sign-in Method (you may see Microsoft Authenticator listed already but this is for your old device)
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Click the drop down arrow for options
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Choose from the options provided
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Choose authenticator app.
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Select Show QR Code
Authenticator app only provides a place to enter code and URL, please see note above to allow camera access
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Scan the code and your account will add, continue to follow the prompts
You may delete the old device now from https://mysignins.microsoft.com/Security Info