Helping debug system hangs

If your Chromebook appears hung (i.e. the screen is frozen and the keyboard and/or trackpad are unresponsive), try the following steps:
  • Press Alt+VolumeUp+X. If you're using a Chromebox, use F10 instead of VolumeUp. These three keys need to be pressed in that order. 
    • This should cause the Chrome browser to restart, and it may take a few seconds.  If the system becomes responsive, go to last step.
  • If still unresponsive, press Alt+VolumeUp+X again. 
    • This should cause the kernel to panic-reboot. If the system becomes responsive, go to last step.
  • Press Alt+VolumeUp+R which should cause a warm reset & reboot. If so, go to last step. (This may not work on older hardware.)
  • If the system is still unresponsive, hold the power button for 8+ seconds and the system will power off.
  • Boot the machine, log in, and immediately file feedback using Alt+Shift+i. Make sure that "Send system and app information" is checked.
If Alt+VolumeUp+X worked, you may also be able to see crash report IDs at chrome://crashes.

For a complete and up-to-date list of debug key sequences including those for ChromiumOS devices without a keyboard check here.