Came home, installed TortoiseSvn, rebooted, nothing. A reset didn’t help, still had a black screen saying “Starting Windows” but 15 minutes of starting time is more than enough I think.
Resetted the virtual machine again and followed the Startup Repair guide which does a system test. It asked if I wanted to go to a restore point, which I denied and did a complete checkup which stated that everything was ok and that it was probably a newly installed application that caused the problem. I rebooted the system again planning to use the restore option after all, but now, as by magic, the system booted without any problem.
I also noticed that when using several instances of the same application, in my case Visual Studio, you no longer get all their window headers in your taskbar but they are all grouped under the same icon. Nice.