Android - Windows 10 Fastboot Driver

By looking at the inf file, you can find that it tells to use the WinUSB driver. So there is a better solution than disabling driver signature enforcement, you can use the tool Zadig (http://zadig.akeo.ie/). This tools create a self-signed inf for this specific device, using ephemeral keys, added to the trusted certificate store (for this only device / inf), removing the need to disable signature check.

So you can do this :

1. Download the tool, start it.
2. Select the "S1Boot fastboot" device
3. Select the WinUSB Driver
4. Click Install

And then fastboot devices list your device.

I found the solution myself: Windows 10 somehow does not want to install the driver, as it can not verify the manufacturer. So the driver from Sony Developer's site works just fine. After deactivating the Windows driver signature check everything works fine.

To deactivate proceed like this: (taken from HERE)

1. Press Win + X then U then Shift + R
2. Once your Computer has rebooted you will need to choose the Troubleshoot option
3. Then head into Advanced options
4. Then Startup Settings
5. Since we are modifying boot time configuration settings, you will need to restart your computer one last time
6. Here you will be given a list of startup settings that you can change. The one we are looking for is “Disable driver signature enforcement”. To choose the setting, you will need to press the F7 key