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C#•3y ago•
3 replies
DR-Ant-Boy

❔ System.Io.Ports: The given port name (COM4) does not resolve to a valid serial port.

Hi, I've been using System.Io.Ports to connect to a USB thermal printer that I have connected to my computer. When trying to open the port to print, the functionality was working as expected and printing the documents, but after a day it started throwing the error mentioned above, and ever since i have not been able to open that port anymore because it says that the name is not valid.
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