Every time I get an Windows 11 update, my lighburn software has an issues with assigning the device. I get “connection failed COM Port busy”. I uninstalled Lightburn on re-install I get a "cannot exe error code 740. Microsoft says its a Lightburn issue, but it work before the update. How do I get passed the 740 error code?
Of course they do. The request for a COM port is Lightburn. Assigning the COM port is all Microsoft. Lightburn, or any other software, has no control over that.
Open the Windows Device Manager, then connect the laser and disconnect it. You should see a USB connection with CH340 in it appear, and go away when you unplug the laser. It will also show you which COM port to select in Lightburn if there is more than one.
If this fails, you have either a bad cable or bad COM port. Not a bad Lightburn.
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