Yepp, epic fail, I didn’t take a snapshot before I upgraded a 15.4 to 15.5 according to this how-to
After reboot only a black screen with a non-blinking cursor in upper left corner comes up after grub menu and last message in console was “Locale service” or alike (changes with every boot I try). The graphics adapter is VBoxSVGA, the host has a
03:00.0 VGA compatible controller: NVIDIA Corporation GF119 [NVS 310] (rev a1)
with TW (latest) as OS.
Any Idea how to debug this?