# Setting Up QGroundControl

When QGroundControl starts, it grabs up all the COM ports on the computer and hangs onto them. Windows and Linux only allow one application at a time to own a COM port, so once QGroundControl has the ports, CeruleanTracker can’t get at the ROV Locator Receiver or the GPS. Follow these instructions to tell QGroundControl to leave the COM ports alone. This will not have any effect on the way a BlueROV2 operates.

Requirements:

* QGroundControl >= 3.5.2
* BlueROV2 with a recent version of Companion

Open the Q menu of QGroundControl, and find the section about 1/3 of the way down that looks like the picture below. Change the settings so they look like the following picture:

{% hint style="info" %}
Note: Each time you upgrade QGroundControl you may have to repeat this process.
{% endhint %}

![Q Part of the Q menu of QGroundControl](/files/eC1DPrAWt5u9e1kumdhC)


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