Had installed Shelter App, this a second User environment or Work Profile.
The Second user is encrypted with extra User Password, which my version of TWRP could not decrypt.
It is discussed in here GitHubForTwrp
A script is mentioned also which would remove folders.
I did uninstall Shelter App and deleted following folders "10" is ID for additional ...
There is nothing wrong with your backup. You are just impatient. Please ignore WARNING adb backup is deprecated... Now Unlock your device and confirm... that is just because the adb.exe doesn't know what's going on at phone side.
You should see TWRP backup starting at phone display immediately without any confirmation
watch the backup.ab growing until backup ...
basically root method is pretty generic. the leading tools are
in that the order, where former one is recommended for all devices and ROMs while the last is ROM specific
However, while the rooting process is nearly the same, every device is different and there is no generic root method. First you need to unlock ...