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Autehntication failure with UNKNOWN reason...

In the report of Failed attempts, I see that user authentication is failing with the reason "Unknown reason". ACS is mapped into NDS, and this is happening only to new users... Old user are quite fine. The version of ACS is 2.4.

Any idea?

Sasa Vidanovic


Re: Autehntication failure with UNKNOWN reason...

Often times complex troubleshooting issues are best addressed in an interactive session with one of our trained technical assistance engineers. While other forum users may be able to help, it’s often difficult to do so for this type of issue.

To utilize the resources at our Technical Assistance Center, please visit and to open a case with one of our TAC engineers, visit

If anyone else in the forum has some advice, please reply to this thread.

Thank you for posting.

New Member

Re: Autehntication failure with UNKNOWN reason...


Did you have already tried to increase the login detail (System Config/Service Control/Level of Detail/full) after the test it is better to put it back to the initial level. Then you can take a look into the log file located into the CSAuth/logs Folder sometimes you can find additional infos into this log file.


Marc Halleux.

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