In order for integrated security to be used to connect to the database, you must set the Application pool to use a domain account to run under.
To make these instructions simpler, we will name the domain account RDMRunner, please adapt to your requirements.
•Create the RDMRunner account in the domain;
•Grant access to the SQL Server instance to RDMRunner;
•Grant access to the database to RDMRunner;
•In IIS Manager, expand the Application pool section and locate the application pool used by your Devolutions Password Server site. By default it has the same name as the name of the web application;
•In the advanced settings, edit the Identity setting to set the RDMRunner account.
Application pool Identity