@Siegfried Heintze Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
I understand that you are facing an error while trying to log in to your Azure AD-protected web application. The error message they received is
The requested content does not exist. with a
404 error code. You have tried several troubleshooting steps, including checking the app registration, creating a new SUSI flow, and changing the redirect URL, but the error persists.
I looked at the above failing error request ID
47e5d2b1-501e-000d-3097-0e80a4000000 in our backend logs. This error is specific to the Azure storage static HTML.
Within your Azure Storage account (stgstXXXXXXXapim) Static website ensure that you have added the index.html page as shown below:
Also for the signin please try hardcoding the complete url as shown below:
Hope this helps.
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