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Communication has been down after changing the USB port.

After installing the Active USB-COM Port Driver, we hooked CU-921 up to the PC and it functioned normally. Following the changes in the installation environment, we re-connected CU-921 to a different USB port, but since then the communication has been down.
We checked the device manager and “DENSO WAVE Active USB-OM Port (COM3)” was still “Disconnected.”

Active USB-COM Port Driver needs to be installed for each port to which the devices will be connected.
Remove all USB devices currently attached to those ports, and re-install the driver to each port.


If it is unknown which port the device will be hooked up to, the driver should be installed to all USB ports.


For the detailed installation procedure, see Active USB-COM Port Driver Installation Guide.

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