You´ll find it here:
Also you could search it under:
Information>Download>Software & Drivers>easyTRX3
Please connect the USB cable to your PC or Laptop directly to a free USB slot.
Using an external USB-Hub, we recommend to use one with an own external power supply.
After connected well, you should see an COM-Port within the Programming-Tool.
Try the highest number first. If its not the right, just select another and press “Connect”.
You´ll be forwarded to the next page automatically.
If you don´t see any COM-Port please try to use another USB-Slot directly on your PC/Laptop.