There are several settings options:

• Switch the UI language between English (en) and Deutsch (de).
• Enable & disable IODDfinder portal remote loading support before make an attempt to search it locally (the next step).
• Add paths to the local search catalog to load IODD files automatically if IODDfinder portal is disable or required IODD wasn't found.
• What roles to display for IODD files ('Operator', 'Maintenance', or 'Specialist', by default all of them are selected).
• Web proxy server in order to check for updates and to load IODD files remotely from IODDfinder portal.
• Check for updates at start-up (support for corporate web-proxy not yet implemented).

All these settings and some another parameters like last open IODD files are stored in 'C:\Users\%username%\AppData\Local\iqPDCT\settings.properties'. Usually avoid to edit this file directly!