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- It is obvious, but it needs to be said: Check whether the username and the password or the secret are correct.
- This error message can also be displayed when the option disable the login to this account is activated for this user. So please go to Setup > Users > Users in Checkmk and check if you see the following icon in the row for the user you are trying to authenticate with:
In this case, you have to edit the user and deactivate the checkbox in front of disable the login to this account.
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