Right-click the device in Device Manager > Update Driver > Browse my computer > Let me pick > Select the CH340 driver (not the USB Serial Port). B. "Port Already in Use"
C. Recommended diagnostic checklist (one-page) cutting plotter 721 driver windows 10
Your cutting software (like SignMaster, ArtCut, or Flexi) says "Port in use" or simply "No device found." Right-click the device in Device Manager > Update
To download the driver, you can try the following options: you can try the following options: