Depending on the date of purchase of your license, your dongle has feature 19 or feature 21 activated for time-resolved Brillouin light scattering measurements using a Time Tagger from Swabian Instruments.
Thus, after downloading the software if a license error occurs on the first startup even though the USB donlge is present, you need to manually select the feature. To do so, select File => License setting from the menu bar and select Feature 19 or Feature 21 according to your license and restart the application.