how do i use my authenticator app in a new device?

Dear @Nathan Nathan,

Good day! Welcome to Microsoft Q&A forum!

Based on your description, I understand that you recently purchased a new mobile device and installed the Authenticator app, but you’re having trouble adding your school Microsoft account because it’s asking for a verification code from the Authenticator app that you don’t know how to obtain, which is preventing you from signing in to your account.

I sincerely apologize for the inconvenience caused by this issue.

Regarding this situation, please kindly try the following steps to set up Microsoft Authenticator for your new device:

• Sign in to the 'Security info' page of your work or school account at mysignins.microsoft.com/security-info
• Select 'Add sign-in method'
• 
• Choose 'Microsoft Authenticator'
• 
• If you already have Authenticator installed on your phone, select 'Next' to display a QR code
• From there, open Authenticator app on your phone and select the plus icon and select 'Add account'
• Select 'Work or school account' then tap 'Scan QR Code'
• 

If you can't access the Security info page, you might need to reach out to your IT Admin for assistance. If you’re unable to sign in due to a phone change, a new phone number, or issues receiving your authentication code, your IT administrator can help by updating your authentication methods or revoking and re-registering your authentication.  

Please note that forum moderators have no control over user accounts, especially when it comes to logging in to your account, resetting your password, changing your access, etc.  

For detailed guidance, ask your IT administrator to review the step-by-step instructions provided in the referenced article: Manage user authentication methods for Microsoft Entra multifactor authentication

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.

Kindly let me know when there are updates or if you need further assistance. Any updates you’re able to share would be really helpful.

I'm here and happy to help! Thank you for your kindness and patience!

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To use the Microsoft Authenticator app on your new device, you will need to follow these steps:

1. Install the Authenticator App: Ensure that you have downloaded and installed the Microsoft Authenticator app on your new mobile device from the appropriate app store (Google Play for Android or App Store for iOS).
2. Sign in to Security Info: On a web browser, sign in to your Microsoft account and navigate to the Security info page. You may need to use another method of verification if you cannot access the Authenticator app.
3. Add Sign-in Method: On the Security info page, look for an option to add a new sign-in method. Choose to add the Authenticator app.
4. Follow the Prompts: You will be prompted to open the Authenticator app on your new device and complete the setup process. This typically involves scanning a QR code or entering a setup code.
5. Access the Code: Once the setup is complete, the Authenticator app will generate a verification code that you can use to sign in to your school account.

If you are unable to access your account because you do not have the code from the old device, you may need to contact your school's IT support for assistance in resetting your multi-factor authentication settings or for alternative verification methods.

References:

• Authentication methods in Microsoft Entra ID - Microsoft Authenticator app
• Register passkeys in Authenticator on Android or iOS devices