Comment 19 for bug 1783267

I tried your suggestion in #17 and uninstalled (purged) virtualbox-guest-dkms-hwe and rebooted on kernel 4.15.0-30. Result: my system is just as broken as before, virtualbox-guest-utils-hwe.service also fails to start and my screen remains black after that (I suppose X doesn't start either). So there is definitely an incompatibility between virtualbox-guest-*-hwe packages and the latest HWE kernel on xenial now.