Problem to switch to FP Open

looking at the installation guide, I thought it’s simple to install FP Open. I try to install from Win7 using the manual switcher. Phone is connected, script starts,

"fairphone open 18.02.0 Manual Flashing Script
Validating files…
All files ar valid,
One device in fastboot mode is connected.
Are you sure you want to wipe all user data and settings on the phone?
Type “Yes” to continue: "

once I type “yes” and enter script ends itself. How I can get the installation to run?

A post was merged into an existing topic: Open OS Manual Flashing Script does not work