I got "User authentication failed", when entering the KDS diagnostic function

○ Symptom: When entering the KDS diagnostic function,

                       you got the “User authentication failed”

○ Solution1. Relog-in KDS

1. Log out of KDS.

2. Close all apps running on the tablet, including KDS.

3. Run KDS and log in, then try again.

         If the above method does not resolve the issue,

         follow the Solution2 below:

○ Solution2. Delete the data and cache of the KDS app.

1. Log out of KDS.

2. Close all apps running

    on the tablet, including KDS.

3. Go to the path on tablet PC.

    Path: (Android) Settings -> Apps -> KDS2.0/KDS -> Storage

4. Select Clear Data or Clear Cashe to proceed with deletion.

     (All inspection data saved on the tablet will be deleted)

5. Run KDS and log in, then try again.