Go into your PCs bios and make sure the Serial Port is not disabled:

Then install the COM Port in Windows like this.
-Open "Device Manager"
-Select menu "Action" -> "Add legacy hardware", then Click "Next"
-Select "Install the hardware that I manually select from a list (Advanced)" -> then click "Next"
-Scroll down, then select "Ports (COM & LPT)", then click "Next"
-Select "Manufacturer" as your need, (in this case, I'm selecting standard type or default option) then click "Next"
The COM port should be in the device manager even if nothing is connected to it so that is your problem right there.