First download the firmware file to your computer.

1. Connect testo 440 to your computer using a micro-USB cable. The "AutoPlay" window opens.
2. Click Open folder [Open folder to view files] to view the files. A window with the device’s file folders opens.
3. Drag the firmware file into the open window.
4. Disconnect testo 440 from the computer when the copying process is complete.
5. Switch off and restart testo 440. The firmware is installed automatically.