Hi, the issue is solved, but the culprit still is unknown.
In .cache/ I couldn't find anything related to Virtualbox. Everything in VirtualBox VMs/ was touched before Virtualbox failed. After restoring .VirtualBox/ starting a VM still failed. I removed the complete Arch install and excepted of VirtualBox VMs/ I restored everything from a backup that was made when Virtualbox still worked. After doing this Virtualbox could start a VM :). After restoring /home from the state when Virtualbox already failed, Virtualbox still was able to start a VM :). After updating everything excepted of systemd Virtualbox still can start a VM. I suspect that a random issue caused by Virtualbox or updating systemd is the culprit. Regards, Ralf
