I have the problem that I can not install drivers for the device to get into fastboot mode to load TWRP on it. Under Device Manager is written "S1Boot Fastboot" with exclamation mark and also "Android ADB Interface" (see picture).
Now I tried the following things to load the driver on it:
1) There is an ADB installer on the website:
15 seconds ADB Installer v1.4.3 ADB, Fastboot and Drivers What is this? This is All-in-One installer for 3 most needed PC tools for Android. No need to download big SDK for 3 small things. I originaly made it for my Kurdish friend AnGrY DuDe in...
2) Flashtool. But here I don't get further after the installation, a window opens, where I should enter a directory, but the message comes again and again although I set the given path (see picture).
3) Via Android Studio - SDK Master - SDK Tools - Google USB Driver.
4) Manually loading the drivers via Device Manager, as described here:
Download Sony Xperia Z4 Tablet USB Driver, Android ADB Driver, and Android Fastboot Driver for Windows 10/8.1/8/7 and XP PC or Laptop Computer.
But none of these methods worked for me, I don't know what I'm doing wrong.
One thing I do know is that I had rooted the device before and loaded LineageOS 14.1-20170804 unofficial-karin on it. How I did that with the drivers back then, I don't remember, because its been a while.