Hi, 2015-04-20 virtualbox [1] still could start a guest. After closing Virtualbox I upgraded kdebase-runtime (15.04.0-3 -> 15.04.0-4) thunar (1.6.6-2 -> 1.6.7-1) and then shutdown Arch Linux to make a backup of this Arch Linux install. 2015-04-21 I used Arch Linux again and upgraded kdebase-lib (15.04.0-1 -> 15.04.0-2) perl-file-basedir (0.06-1 -> 0.07-1) sip (4.16.6-1 -> 4.16.7-1) python-sip (4.16.6-1 -> 4.16.7-1) python2-sip (4.16.6-1 -> 4.16.7-1) libxfcegui4 (4.10.0-4 -> 4.10.0-5) libsystemd (217-8 -> 219-5) systemd (217-8 -> 219-5) systemd-sysvcompat (217-8 -> 219-5) lib32-systemd (217-1 -> 218-1) reinstalled linux (3.19.3-3) upgraded libvpx (1.3.0-1 -> 1.4.0-2) ffmpeg (1:2.6.1-3 -> 1:2.6.2-1) ffmpeg-compat (1:0.10.15-2 -> 1:0.10.16-1) firefox (37.0.1-2 -> 37.0.2-1) gd (2.1.1-1 -> 2.1.1-2) graphviz (2.38.0-3 -> 2.38.0-4) gst-plugins-good (1.4.5-1 -> 1.4.5-2) gstreamer0.10-bad (0.10.23-8 -> 0.10.23-9) gstreamer0.10-bad-plugins (0.10.23-8 -> 0.10.23-9) vlc (2.2.1-1 -> 2.2.1-2) libkolab (0.5.3-1 -> 0.6.0-1) mencoder (37379-2 -> 37379-3) mplayer (37379-2 -> 37379-3) xine-lib (1.2.6-4 -> 1.2.6-5) After that I wanted to use Virtualbox, but it can't start a guest anymore: "Failed to create a new session. Callee RC: NS_ERROR_FACTORY_NOT_REGISTERED (0x80040154)" If I run Virtualbox in a terminal I get "Qt WARNING: libpng warning: iCCP: known incorrect sRGB profile" already before I try to start a guest. After some WWW inquiries I disconnected USB of an iPad and of an external WD from the computer and rebooted to clean /tmp, but this didn't solve the issue. Then I tried some Voodoo by running $ sudo mv /boot/initramfs-linux-rt-lts.img /boot/initramfs-linux-rt-lts.img.bak $ sudo mv /boot/initramfs-linux-rt-lts-fallback.img /boot/initramfs-linux-rt-lts-fallback.img.bak $ sudo mkinitcpio -p linux-rt-lts and a reboot, but nothing changed. I continued doing nonsense by downgrading systemd to the version I used the last time running Virtualbox. The remove was needed for the downgrade $ sudo rm /etc/systemd/system/multi-user.target.wants/remote-fs.target libsystemd (219-5 -> 217-8) systemd (219-5 -> 217-8) systemd-sysvcompat (219-5 -> 217-8) lib32-systemd (218-1 -> 217-1) in addition I restored initramfs $ sudo rm initramfs-linux-rt-lts-fallback.img initramfs-linux-rt-lts.img $ sudo mv initramfs-linux-rt-lts.img.bak initramfs-linux-rt-lts.img $ sudo mv initramfs-linux-rt-lts-fallback.img.bak initramfs-linux-rt-lts-fallback.img and rebooted. Despite all the Voodoo Virtualbox still fails and all cats and chickens in the neighbourhood are still alive. Arch is up to date [2]. Any hints are welcome. Regards, Ralf [1] $ pacman -Q virtualbox linux-rt-lts virtualbox 4.3.12-1 linux-rt-lts 3.10.61_rt65-1 I need this old Virtualbox, because new versions of Virtualbox faile, when I try to update my iPad's iOS by USB, running iTunes on a XP guest. Building Virtualbox modules with dkms for new kernel versions fail, so I run it on a LTS RT kernel. [2] $ sudo pacman -Syu [snip] :: Starting full system upgrade... warning: ardour: ignoring package upgrade (2.8.16-1 => 3.5.403-1) warning: clthreads: local (2.4.0-5) is newer than community (2.4.0-1) warning: gvfs: local (2013.08.18-1) is newer than extra (1.24.1-1) warning: lib32-systemd: ignoring package upgrade (217-1 => 218-1) warning: libfishsound: local (1.0.0-2) is newer than community (1.0.0-1) warning: libsystemd: ignoring package upgrade (217-8 => 219-5) warning: linux-rt: ignoring package upgrade (3.18.9_rt5-2 => 3.18.11_rt7-1) warning: linux-rt-docs: ignoring package upgrade (3.18.9_rt5-2 => 3.18.11_rt7-1) warning: linux-rt-headers: ignoring package upgrade (3.18.9_rt5-2 => 3.18.11_rt7-1) warning: linux-rt-lts: ignoring package upgrade (3.10.61_rt65-1 => 3.14.36_rt34-1) warning: linux-rt-lts-docs: ignoring package upgrade (3.10.61_rt65-1 => 3.14.36_rt34-1) warning: linux-rt-lts-headers: ignoring package upgrade (3.10.61_rt65-1 => 3.14.36_rt34-1) warning: ignoring package replacement (mate-calc-1.8.0-2 => galculator-gtk2-2.1.3-3) warning: mate-dialogs: local (2013.08.18-1) is newer than community (1.8.0-2) warning: meterbridge: local (0.9.2-5) is newer than community (0.9.2-1) warning: pulseaudio: local (2013.08.18-1) is newer than extra (6.0-1) warning: sylpheed: local (3.4.2-20141124) is newer than community (3.4.2-1) warning: systemd: ignoring package upgrade (217-8 => 219-5) warning: systemd-sysvcompat: ignoring package upgrade (217-8 => 219-5) warning: virtualbox: ignoring package upgrade (4.3.12-1 => 4.3.26-3) warning: virtualbox-guest-iso: ignoring package upgrade (4.3.12-1 => 4.3.26-1) warning: virtualbox-host-dkms: ignoring package upgrade (4.3.12-1 => 4.3.26-3) warning: zita-alsa-pcmi: ignoring package upgrade (0.2.0-1 => 0.2.0-2) warning: zita-resampler: ignoring package upgrade (1.3.0-2 => 1.3.0-3) there is nothing to do