Choose a COM port for a Bluetooth enabled device

Some computer programs require a COM port (also called a serial port) to communicate with a Bluetooth enabled device. This might include:

  • A program that synchronizes contacts with a mobile phone.

  • A program that extracts Global Positioning System (GPS) coordinates from a GPS receiver.

When you add a Bluetooth enabled device to your computer, this often creates an incoming COM port and an outgoing COM port. The incoming COM port permits your device to connect to a program on your computer, while the outgoing COM port permits a program on your computer to connect to your device. Usually, you only need to use one of these COM ports. For more information, see Add a Bluetooth enabled device to your computer.

To decide which COM port to use, you can check the information that came with the program or your Bluetooth enabled device, or you can go to the manufacturer’s website. Most Bluetooth enabled devices select a COM port to use, so you don't have to do this. You can check to see if a device is already using a COM port on the COM Ports tab of your Bluetooth settings. For instructions about opening this tab, see below.

If you need to select a COM port and are unsure of which one to use, try each COM port one at a time and use the one that successfully allows the program and your device to communicate.

To change which COM port your computer uses to communicate with Bluetooth enabled devices

  1. Open Control Panel by clicking the Start button Picture of the Start button, and then clicking Control Panel.

  2. In the Control Panel search box, type Bluetooth, and then click Change Bluetooth settings.

  3. In the Bluetooth Settings dialog box, click the COM Ports tab, select a port, and then click OK.

    If no COM port is listed, then your Bluetooth enabled device doesn't use a COM port. Click Add if you want to add a COM port for your device to use.

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