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Make sure the CoreOne Suite Account and the provisioning configuration where you want to use Integrated Windows Authentication have different Usernames.
For the Active Directory this means the Sam-Account-Name has to be different than the Username of the CoreOne Suite Account.
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Step 4 - IIS Settings
Enable Windows Authentication in IIS for the site where the CoreOne Authentication Service according to this link: https://docs.microsoft.com/en-us/iis/configuration/system.webserver/security/authentication/windowsauthentication/
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