It is essential to turn off the inbuilt Bluetooth before plugging in the BT820. Some computer manufacturers provide a hardware switch to turn off the inbuilt WLAN and Bluetooth (Figure 1), while others may require the user to press a combination of keys and select which wireless connectivity to be disabled (Figure 2).
Figure 1: Hardware switch
Figure 2: Combination of keys
Information on how to turn off the inbuilt Bluetooth hardware should be available in the computer user manual.