Hi @m_amann and welcome to the Knime Community.
Can you show us how you are using the Connector? Can you show us the settings you are using?
For using your windows credentials to connect to MSSQL, you should use the None/native authentication option for Authentication:
For integratedSecurity, if it’s needed, you can add it as a JDBC parameter like this:
Click on the Add button, and it will allow you to add an entry. Just add integratedSecurity as Name and true as Value