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Understanding Azure Built-in Roles’ Impact on User Authentication Methods Blade

Use Microsoft Error Lookup Tool to Decode MS Error Codes

Troubleshooting ADFS Azure MFA Adapter

Capturing the HTTP trace using Fiddler / Browser F12

Capturing the Authentication Trace

Capturing the ADFS Diagonostic Logs

Grant B2B users in Azure AD Access to On-premises Applications (AADAP)

Common DRS Error Codes & Possible Troubleshooting Guides