Failed to open the serial port: Error: I/O error setting custom baud rate of 115200 (ZW0100)

I am new to Home Assistant and I wanted to set it up to control my Z-Wave devices.

I have installed Oracle VM VirtualBox Version 7.0.6 r155176 (Qt5.15.2) on a Windows 10 laptop. I then set up Home Assistant under VirtualBox. I have an Aeotec Z-stick Gen5 which shows up as residing on port COM3.

I installed the Z-Wave JS UI AddOn to Home Assistant. However whenever I start the Z-Wave JS UI interface I get the “Failed to Open” error. I have tried setting the device to /dev/ttyS0 through S3 and keep getting the same error.

I’ve seen several similar posts with suggestions of checking my HA port but no one says where to check this. I’d like to know where to find what address Virtualbox/HA is looking for to open.

I did see one suggestion to install the VirtualBox extension pack but that did not seem to fix the problem.

None of those are USB serial ports. You need to configure USB passthrough so the VM can see the USB stick. You certainly need the extension pack to do that. There are a ton of guides on how to setup USB devices.

Also, last time I tried Virtualbox 7, USB passthrough was not working properly. Reverting back to v6 worked fine. So watch out for that.

Where do I configure USB passthrough? Also can you point me to some of these guides? None of my Google searches or forum searches have given me any definitive sources.

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