@z4tab
Today, I also got SGP771 and installed ubuntutouch!
As a result, I get the exact same error as you and it stops at the "adb is scanning fordevices" screen.
I think this is a bug, since both you and I have the same symptoms.
You need to report this somewhere and ask for support!

@nero355 　Thanks
The installation of ubuntu touch failed.
I used ubports-installer_0.8.9-beta_win_x64.exe
I used Flashtool because xperia can be unlocked by using Flashtool software.
I used Flashtool because xperia can be unlocked using Flashtool software. o Developer mode of tablet is ON. o OEM unlock and USB debugging are ON.
Is ubports-installer_0.8.9-beta too new? Is ubports-installer_0.8.9-beta newer or should it be older?
Is the run/start ADB the result of running in power shel?

Do I need to install TWRP on the tablet before running ubports by any chance?

I'm sorry, but the procedure to install ubuntutouch on this tablet is

Turn on OEM unlock and USB debugging in developer mode
Look up the IMEI (or IDID) and get the code needed for Unlock
Use flashtool to unlock the bootloader

Is this next step to install ubuntutouch with ubports installer already?
Or do we still need to prepare?

@lakotaubp
Thanks, I've never used 15 sec adb before, I'll try it.

@z4tab
Today, I also got SGP771 and installed ubuntutouch!
As a result, I get the exact same error as you and it stops at the "adb is scanning fordevices" screen.
I think this is a bug, since both you and I have the same symptoms.
You need to report this somewhere and ask for support!

@aarontheissueguy
Thank you.
But unfortunately the one I downloaded was already
ubports-installer_0.8.9-beta_win_x64

@moem
I'm sorry if I offended you, but is that true?
Isn't it only the SGP771 model sold outside Japan that is supported?

It says xperia z4 tablet is one of the supported devices.
I have an xperia z4 tablet wi-fi (SGP712), but it stops in the middle of the process with the message [adb is scanning for devices].
Isn't the xperia z4 tablet wi-fi not compatible with the SGP712?

https://devices.ubuntu-touch.io/device/karin/

I bought the Sony Xperia Z4 Tablet wi-fi version "SGP712JP" with no worries because of what it says here!
I excitedly booted up the android tablet that arrived and turned on developer mode, OEM unlock and USB debugging.
I downloaded the windows version of Ubports Intaller [ubports-installer_0.8.9-beta_win_x64.exe] and installed ubuntutouch, but the tablet is still dark and the blue LED is glowing.
The installation stops halfway and does not complete.

Is the Sony Xperia Z4 Tablet actually unsupported?

Translated with www.DeepL.com/Translator (free version)