I'm a little confused. As far as I know, you will not see a COM port if the device is not recognised. So COM5 is more than likely not your Uno.
If your Uno does not use the 16U2 TTL-to-USB converter, the board will not be recognised as an Arduino Uno but as a serial device.
In below image, a genuine Uno with 16U2 is on COM8, a SparkFun RedBoard with a FT232 is on COM5 and a clone Nano with CH340 chip is on COM10.
Not always for clone boards. Arduino does not produce boards with CH340 so they don't supply the driver for that.