A VM runs into a Guru Meditation if there is a problem which cannot be fixed by other means than terminating the process. The default is to show a message window which instructs the user to open a bug report.

This behavior can be configured as follows:

$ VBoxManage setextradata VM-name GUI/GuruMeditationHandler mode
                  

mode is one of the following:

Default

A message window is shown. After the user confirmed, the VM is terminated.

PowerOff

The VM is immediately powered-off without showing any message window. The VM logfile will show information about what happened.

Ignore

The VM is left in stuck mode. Execution is stopped but no message window is shown. The VM has to be powered off manually.

This is a per-VM setting.