Install and use the SecureDFU firmware update

Some K780, K375s, and K850 keyboards may experience the following:

• When your keyboard is in sleep mode, it takes more than one keypress to wake it 
• The keyboard enters sleep mode too quickly

If you are experiencing this problem, please download the Logitech Firmware Updating Tool (SecureDFU) from your product's Download page and follow the onscreen instructions.

NOTE: You’ll need a Unifying receiver to perform the update.

Install and use the SecureDFU tool

1. Download and open SecureDFU_x.x.xx and select Run. The following window appears: 

   

   NOTE: During the firmware update process, Unifying devices will be unresponsive.
2. Click CONTINUE until you reach the window shown:

   

3. Click UPDATE to update your device. It’s important to not disconnect your keyboard during the update, which may take several minutes.

   

4. Once the update is finished, the DFU tool will prompt you to update your Unifying receiver.

   

5. Click UPDATE.
6. Once the update has finished, click CLOSE. Your device is ready to use.