I too am unable to install the USB driver. I get the following error: "Cannot create DRVSETUP64\DRVSETUP64.exe"
I check device manager and I have USB-Serial CH340 (COM3) and when I check the details, Hardware Ids I have "USB\VID_1A86&PID_7523&REV_0264" and "USB\VID_1A86&PID_7523".
If you have COM3 present in device manager with right VID/PID, the driver is already installed and good. VID/PID is VendorID/ProductID, is what windows use to attach a specific driver to a specific device.
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