Try connecting with a different USB port, and/or power cycling the computer. The FTDI driver for Mac has been known to conflict with Apple’s own internal virtual serial port driver, and it can end up locking out the port.
Try connecting with a different USB port, and/or power cycling the computer. The FTDI driver for Mac has been known to conflict with Apple’s own internal virtual serial port driver, and it can end up locking out the port.