It seems the integration setup went by ID:
“/dev/serial/by-id/usb-Nabu_Casa_ZBT-2_DCB4D90C2F2C-if00”
Let me know if I have it wrong… and yes switching to USB 2…
Thanks
Nope, you got it absolutely right
I had the same issue with the failure to install firmware (in my case, Matter). My Odroid N2 just has USB3 sockets, but I found that the problem was the cable. I originally had the cable that came with the ZBT-2 plugged into another extension lead and I could not install the firmware (even after updating the firmware usaing the Device Toolbox). I swapped extension leads, with no change, and it is only when I plugged the ZBT-2 directly into the Odroid with the supplied lead that it would work.
Hopefully this will help someone else!
Hi Jinieren,
Your post looks really promising! i am struggling to get my new ZBT-2 working with HA in ESXI.
I have tried your steps and manually installed the ’ [zbt2_openthread_rcp_2.4.4.0_GitHub-7074a43e4_gsdk_4.4.4.gbl](https://github.com/NabuCasa/silabs-firmware-builder/releases/download/v2025.11.24/zbt2_openthread_rcp_2.4.4.0_GitHub-7074a43e4_gsdk_4.4.4.gbl’ as i want to use thread instead of Zigbee.
as i connected it for the milionth time to my HA instance i rebooted the instance and tried to add the device and choose voor threads. To my surprise HA still wanted to install threads firmware like i did not do that a few minutes back. And still one big fat error message like 30 seconds later.
Update 22:13:
I think i need to add more info.
So my HA runs on Esxi 8.0 update 3 on a Intel nuc. The ZBT-2 is attatched to a usb 2.0 port and esxi configured 2.0 port.
when i attatch the zbt to my laptop and use the firmware website i cant force the 7.4.4.5 firmware on it by manualy uploading a firmware file. i only get the ‘default’ zigbee which will be 7.4.4.6 or the default threads firmware installed on that sucker… ran it in up to date versions of edge and chrome with any form of blocker add in turned off…
Still when i connect to HA and either choose threads or Zigbee it wants to install that firmware and fails…
running HA 2025.12.5 as OVA in Esxi
Actively pulling out my last few hairs…
Nice! Fixed it!
Updated HA core to the 2026.1 and added the ZBT-2 by mobile app.
I would say the firmware did fix my problem but maybe the add process by mobile app goes smoother. did not try it by app earlier this week so i don’t know what fixed it… but it did!
Well, that is pretty sad when a brand new device in 2026 with a USB-C port does not work on a USB3 port! Hopefully Home Assistant folks will figure this out soon.
I have a Home Assistant Blue and it only has USB3 ports.
I plugged the ZBT-2 into my Mac (yes, a USB3 port) and ran the Web Updater pointed to in other threads. This worked fine. It installed the latest Thread firmware no problem.
However, when I then plugged the ZBT-2 back into the HA Blue, HA discovered it and then tried to install firmware again(!) and it failed again. Sigh.
Any ideas on how to get this to work?
I also purchased a ZWA-2 but haven’t tried setting it up yet. Hopefully it does not have the same issue…
I also just tried using the iOS mobile app - same issue.