Hi @Jose Ponce
Thank you for posting this in Microsoft Q&A.
I understand that you are facing an issue with accessing SharePoint and receiving an error message "AADSTS50011: The redirect URI 'https://[mycompanyname].sharepoint.com/_forms/default.aspx' specified in the request does not match the redirect URIs configured for the application '00000003-0000-0ff1-ce00-000000000000'. Make sure the redirect URI sent in the request matches one added to your application in the Azure portal."
This error occurs if the redirect URI (reply URL) configured in the application (code) and the Microsoft Entra app registration don't match.
To fix the issue, follow this document https://learn.microsoft.com/en-us/troubleshoot/azure/active-directory/error-code-aadsts50011-redirect-uri-mismatch#resolution
Hope this helps. Do let us know if you any further queries.
Thanks,
Navya.
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