Symptoms
A virtual machine hanged, it is impossible to stop/restart it from the GUI, because all the buttons are grayed out.Resolution
On the Host computer open Terminal application from Finder -> Applications -> Utilities and copy/paste the following command:ps auxwww | grep prl
Hit Return and you will see a list of Parallels processes like the one below:
administrator 362 44.3 4.9 594924 77396 ?? R 9:52AM 0:16.80 /Library/Parallels/Parallels Service.app/Contents/MacOS/../PlugIns/Parallels VM.app/Contents/MacOS/prl_vm_app 78 {248e9848-2169-4aa6-bfbf-c53c3db5c752} {b08e2690-ca2e-4e4b-aeab-449e99edb98e} server
administrator 360 9.1 5.3 735940 82612 ?? U 9:52AM 0:12.26 /Library/Parallels/Parallels Service.app/Contents/MacOS/../PlugIns/Parallels VM.app/Contents/MacOS/prl_vm_app 62 {cae3858f-5863-4e9a-badc-a7af37a43297} {b08e2690-ca2e-4e4b-aeab-449e99edb98e} server
administrator 327 7.5 3.8 929836 59676 ?? S 9:50AM 0:23.71 /Applications/Parallels Management Console.app/Contents/MacOS/prl_client_app -psn_0_106522
root 180 6.1 0.8 119124 12876 ?? S 9:47AM 0:04.32 /Library/Parallels/Parallels Service.app/Contents/MacOS/prl_disp_service -e --logfile /var/log/prl_disp_service_server.log --pidfile /var/run/prl_disp_service.pid
root 165 0.0 0.2 92560 2948 ?? Ss 9:47AM 0:00.08 /Library/Parallels/Parallels Service.app/Contents/MacOS/prl_naptd
prl_vm_app processes are the ones of your virtual machines (all which are in not stopped state - running, suspended, paused etc).
The line in the first curly breaks is the correcpondent machine's UUID ({248e9848-2169-4aa6-bfbf-c53c3db5c752} - for the first machine in our example above).
Issue the second command:
prlctl list -a
Hit Return and you will get a list of all your virtual machines with their UUIDs:
{248e9848-2169-4aa6-bfbf-c53c3db5c752} paused Red Hat Enterprise Linux
{7959a431-e0c1-4380-9887-e766f6e51530} stopped CentOS Linux
{9d9174e1-deed-4d7e-bb14-4e7ad307899f} stopped Ubuntu Linux
{a9b57971-b7d7-4961-b157-10490852cced} stopped Ubuntu Linux 8.10
{b5d933c3-6b41-44f5-b477-dadeb2c2e346} stopped Windows Server 2003
{cae3858f-5863-4e9a-badc-a7af37a43297} running Windows XP
Find out the UUID of the machine you would like to stop and abort the prl_vm_app process of this VM:
sudo kill -9 362
NOTE: You will be asked for Mac administrator's password, though you will not see it when typing.
In case of Parallels Server, please, restart the Parallels Management Console.