Unable to access shared work files wants a code on work network

Good day Rachael, 

The verification prompt is part of the Multifactor Authentication (MFA) security process for your colleague's Microsoft 365 work account. Even when connected to the company network, some sign ins still require additional verification based on your organization's security policies. 

To complete the sign in, your colleague must use a verification method that is registered to their own work account. Codes from your phone won't work unless their account has already been added to your Microsoft Authenticator app. 

If authenticator has already been set up, ask them to open the Microsoft Authenticator app, select their work account and enter the current one time verification code shown in the app. 

If they haven't set up authenticator yet, changed phones, or no longer have access to their previously registered device, they will need to contact their IT administrator. In case they do not know who is the IT admin, kindly refer to this article: How do I find my Microsoft 365 admin? - Microsoft Support   

They can explain: "I am unable to sign in because I cannot complete the Microsoft Authenticator verification and need my MFA settings reset or re-registered" 

Your colleague can also share the steps in this Microsoft article with the IT administrator, which can help them reset your colleague's MFA settings: Manage user authentication methods for Microsoft Entra multifactor authentication.  

Your organization's IT admin can reset the MFA registration and allow them to set up Microsoft Authenticator again. After the reset, they will be guided through the enrollment process, including scanning a QR code to link the app to their account. 

Additional information is available in the following resource: How to add your accounts to Microsoft Authenticator | Microsoft Support 

Once the setup is completed, they should be able to sign in and access OneDrive normally. 

I hope this information is helpful. If you have any questions or need further support, please don’t hesitate to reach out at any time. 

Thank you for your patience and understanding. 

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