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Assigning a COMPort Between 1 and 20

Our hardware will only check for a port between the numbers 1 and 20.  

  • If you are having troubles with the hardware connecting to the computer (receiving an “Unable to connect to ComPort” message) you may need to manually check or assign the port.
  • Check if the device is communicating with the computer:
    • To do this go to Device Manager and check that there is an item under Ports (COM & LPT) called USB Serial Port (COM*)
    • Also, you need an item at the bottom of the “Universal Serial Bus Controllers” called “USB Serial Converter” as shown at the bottom in the image below.
    • If these two items do not appear:
      • Try a different USB cable
      • Try the device on a different computer – (it might be necessary to install the software).
      • If the problem persists you will need to assign/reset the comport (explained below)
  • To reset/assign the COM Port on your computer:
    • Go to ‘Device Manager’ and find the item in the list, if the (COM) number is higher than 20 (the image above shows COM3) double click on the item.
    • Go to the “Port Settings” tab
    • Now click the “Advanced” button
    • Change the “COM Port Number” by clicking the drop down box and selecting any number lower than 20, you can use any number lower than 20 even if it says COM1 (in use)
    • Return to ‘Control Panel’ clicking OK when asked and your Qest4 main screen should now show the red box saying ‘No Client Selected’.

If these steps fail to resolve the problem, you should attempt to update the Device Drivers.  Click the link below that corresponds to your current version of Windows.

Windows 7  

Windows 8 
Windows 10 

There is an outside chance of a hardware failure. Before concluding this is the case, please test the unit on at least 2 computers.