I try to establish a serial connection with my MacBook (High Sierra 10.13.1) and need help. I have a Belkin F5U103V USB-to-serial adapter and want to connect to a HP ProCurve switch. I tried to follow several instructions such as [this one][1] or the installation instructions in the ZIP-archive of [this driver][2] but none of this worked. After the installation of the mentioned driver of my device, all of the instructions I found asked me to use the `ls /dev/tty.*`, `ls /dev/*usb*` or the `ls /dev/cu.*` command to find out the device which is associated with the usb port. This is the step wich fails for me. The `ls /dev/*usb*` command does not return a result at all. The two other commands return >/dev/cu.Bluetooth-Incoming-Port >/dev/cu.SOC >/dev/cu.MALS >/dev/cu.iPhonevonFirstnameLastname-Wire (and the same name with `tty.` instead of `cu.` respectively), which means, that I am not able to find a serial device which is associated with the usb port. After the installation of the driver I had a "USB serial controller" in my network settings. When I change the modem to a "Null modem", set the baud to 9600 and try to connect, a popup appears that says that my device is not available. [![enter image description here][3]][3] Strangely, when I try to connect to the switch via [Serial App][4], I can see the USB serial port and it works perfectly to connect to the switch which means that the USB-to-serial device works fine generally. [![enter image description here][5]][5] I want to open the serial port with the build in `screen` command preferably (`screen <device> <baud>`). What is the reason why I cannot find the device as mentioned in the instructions and how can I use the build-in tools to open a serial connection without 3rd party software? If it is relevant, I have a MacBook Pro 2016 which means that I have USB-to-serial adapter which is plugged in into a USB-c-to-USB adapter. [1]: https://plugable.com/2011/07/12/installing-a-usb-serial-adapter-on-mac-os-x/ [2]: http://www.prolific.com.tw/US/ShowProduct.aspx?p_id=229&pcid=41 [3]: https://i.sstatic.net/NHtGb.png [4]: https://insmac.org/macosx/44-serial.html [5]: https://i.sstatic.net/T39Pq.png