To use SharePoint Server 2019's Secure Store Service, you must complete a few additional steps.
The following steps assume that the Secure Store Service service is already installed and configured as described in the following Microsoft TechNet article: http://technet.microsoft.com/en-us/library/ee806866.aspx.
For more information about the Secure Store Service, see the following TechNet article: http://technet.microsoft.com/en-us/library/ee806889.aspx.
Note:
Mixed-mode authentication on a single page is not supported. OnBase Web Parts using different modes of authentication should not be added to the same page.
Continue to the following procedures: