Error code 500121

Question

Hello, I'm trying to log in to my [Moderator note: personal info removed]

@vetschag.ch account but it requires me to confirm on my mobile device, and I'm trying to log in on it and it's a vicious circle.

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Moved from: Microsoft Security | Microsoft Authenticator

Answer 1

Hello @ROBERT MACHETA

Thank you for reaching out to the Microsoft Q&A forum.  

Based on the information you provided, it appears that you are experiencing an issue where the Microsoft Authenticator app is required when signing in to the account. This issue occurs when sign‑in process was stopped because the second step of verification, such as approving a prompt in your authenticator app, was not completed. In other words, the system was waiting for your second authentication step, but it didn’t go through.  

If you are an administrator, I kindly ask that you request assistance from another administrator in your tenant to reset your authentication method. If you are a standard user, please contact your IT administrator and ask them to revoke your current MFA session and require you to re‑register your authentication methods in the Microsoft Entra admin center. 

Manage authentication methods for Microsoft Entra multifactor authentication

Once the administrator completes the revoke and re‑registration requirements, please delete the existing account entry in your Microsoft Authenticator app before setting up the new configuration. You can do this by: 

1. Opening the Microsoft Authenticator app on your mobile device. 

   

2. Tapping on your work or school account. Selecting the settings icon (gear symbol) in the upper‑right corner and choosing “Remove account.”  This step helps avoid conflicts during the new setup  

After removing the old authentication entry, please sign in to your account again and proceed with configuring the Microsoft Authenticator app as instructed. 

If you have any further questions or need additional assistance, please feel free to let me know. I am here to help.