If you are having trouble talking to your LOR controllers then there is a good chance you are having some issues with the COM port or Drivers needed. This article is designed to help you clear the COM port errors you may be having.


I know, everyone hates the reboot suggestion. However it really is one of the best things to do here. There could be some program running in the background that will cause the COM port to be in use by another service/device but not tell you about it.

After the reboot, make sure that you do not have any LOR show running. To do this look in your Windows system tray and make sure that the LOR icon is RED. If you don’t have one there, then it should be save to assume that your LOR software is not running.

Step 2:  Find the right communications port

Make sure the Light-O-Rama USB485 adapter is connected to a USB port on your computer. For testing you only need one Light-O-Rama controller. Do not try testing with more than one! Disconnect the main power from the Light-O-Rama controller. Connect the Light-O-Rama controller to the USB485 adapter using the data cable.

On the controller plug the cable from the adapter into either of the larger RJ-45 connectors.  If you have three connectors connect to the center or right connector.  The slightly smaller connector is for advanced users.

Once you turn on the controller, the status light on the controller should be flashing or solid on confirming it has power.

Now open the Light-O-Rama Hardware Utility.  This can be found by pressing the Windows Start button/orb and looking in the Light-O-Rama folder.  If the Light-O-Rama sequencing suite is already loaded and running you can also find the Hardware Utility by RIGHT clicking the LOR light bulb in the Windows system tray and you’ll see a secret shortcut list.

In the Light-O-Rama Hardware Utility on the left side is a panel that says ‘Setup Comm Port’.  Click the ‘Auto Configure’ button and follow the instructions.  The Hardware Utility is now scanning the communications port on your computer. If everything was set up correctly, then you will see the Port Number show up there on the left hand side.

If the above was unsuccessful, it’s time to reinstall the low level USB485 low level operating system drivers required by Windows.

If your communications port is Com 17 or higher

Here are some instructions about changing the COM port, should it be higher than 16 when installed. If it is less than 16, you do not need to follow these instructions.

Com ports higher than comm16 are not supported by the Hardware Utility.  You will need to change the port number to a lower value.

The process to change the com port has a number of steps but it is pretty straight forward. There may be slight differences depending on the version of the Windows operating system that you have (XP, Vista, etc… ) but it very similar.

Stop ALL LOR programs and make sure that the LOR USB device is plugged into the PC.

  1. Click the Windows Start button or the Windows “Ball”
  2. Right Click “My Computer” and select “Properties”
  3. Click Hardware if you see a hardware tab
  4. Click Device Manager
  5. Expand Ports (COM & LPT)
  6. Double Click the Com Port that you want to change
  7. Click Port Settings then Click “Advanced”
  8. On the “Advanced” page you will see the COM Port Number. Select a value less than COM17

If all COM ports seem to be in use then pick COM16.

Click OK , OK …. To get out of the Device Manager.