New email in authenticator asks for code while set up

Hi Jurg Banziger, 

Welcome to Microsoft Q&A Forum!

Have a good day and I hope you're doing well!

Thank you for reaching out and sharing the issue you are experiencing when setting up your email with the Authenticator app. I sincerely apologize for the inconvenience this has caused and truly appreciate your patience and effort in trying to resolve it. 

Based on your description, it seems the system is requesting an Authenticator code even though you have not set up Authenticator for this email before. This may happen if two-factor authentication (2FA) was previously enabled on your account, or due to certain security policies. Sometimes, the system may also mistakenly recognize the account as already having 2FA set up. 

To assist you better, could you please let me know: 

• What type of email account are you using? (e.g., company email, Microsoft account, Gmail, etc.) 
• If it is a Microsoft account, have you ever used this account on any other device before? 

If your account is a Microsoft account and you are still signed in on any device, please visit: https://mysignins.microsoft.com/security-info. Here, you can review and remove any unwanted authenticator methods. 

Additionally, please try logging into Outlook via the web to see if the authentication error still appears. If your account is working normally, you may consider removing all accounts from the app and re-adding them to avoid any potential conflicts. 

Once again, I apologize for the inconvenience and truly appreciate your efforts in troubleshooting this issue. If you take any actions or need further assistance, please feel free to let me know. I'm here to support you. 

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