Right click-My Computer-Management-Device Management (at this time, there is no mobile phone and network card plugged into USB, so it is not shown here):

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Then plug in a mobile phone or USB device, and the changes at this time are as follows:

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Click on the port, and you can see the USB port number. At this point, the port number of the computer is 16.

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The above modem port can be connected to this port to access the Internet (this port number needs to be seen in the software used. General port number and modem port number are continuous):