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Click the Delete button in the global configuration for Azure in Alert.
Go to the Azure application that is used for the OAuth connection and revoke the connection.
Re-enter the values for the global configuration for Azure in Alert.
Click the Test Configuration to make sure the configuration is working and the issue is resolved.
To use the standard Alert login functionality (i.e. login as a user stored in the Alert database rather than an external system) when SAML is enabled, append the query parameter ?ignoreSAML=true to the Alert URL in the address bar.
WARNING: Always be sure to secure the passwords of users created in Alert including the default Alert users (sysadmin, jobmanager, alertuser).