This usually indicates a USB detection error.  The easiest way to correct this is:

1. Right-click the iCUE logo in your computer's taskbar and select "Quit".
2. Unplug the K55 from the computer.
3. Plug the K55 into the computer using a different USB stack and open iCUE.

If this does not correct the issue, try a clean reinstallation of iCUE.

If performing the reinstall does not work, please create a ticket for further assistance.