VirtualBox crashes and does not respond at all to BOINC. What can I do?

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If the virtual machine named "boinc_wu_xxxx_..." in the VBox Manager window does not respond at all to BOINC (i.e. you suspend the BOINC task but the VM is still running) you can try the following steps to recover the project:

  1. Abort the running WU and exit BOINC. Then, you will have to manually kill or quit the VirtualBox process from a command line. It will be different in each operating system, but usually:
    1. In Mac OS X: you can kill it using the Terminal interface and running the kill -9 command to kill the PID of the process "VBoxHeadless.exe".
    2. In GNU/Linux: you can kill the VirtualBox process using your Desktop manager or from a terminal using the kill -9 command to kill the PID of the process called "VBox Headless".
    3. In Windows: open the Windows task manager and kill the VirtualBox process.
    4. Restart BOINC: it should receive a new clean WU and everything should be working OK again. If at this point you are still having problems, please use the message boards to get more help.
Detailed question
VirtualBox crashes and does not respond at all to BOINC. What can I do?