Ok, one reboot after my previous message, I was not able to get into Windows at all anymore, not even in Save Mode.
So, I started all over again, this time carefully inspecting the system performance after every step. And I think I have found the cause to my problem.
Could my problem have been caused by turning on “System Cache” performance? That is, under System Properties, on the Advanced tab, open Performance settings, and then on the Advanced tab set Memory Usage to System Cache.
I had once read this setting would be positive for certain computer configurations, but with Avast installed on my computer and turning this settings on, my computer seems to become very instable. This time I was able to boot in Save Mode, I returned the setting to Programs, and after rebooting again my system seems to be stable again.
The weird thing is however that I have another computer with Avast (exact same version) and System Cache mode turned on, and have no problems there…
Any experiences with Avast and System Cache mode?