Knowledge Base - GNOME Boxes
"failed to start" error in Ubuntu 18.04
Make backup copy of qemu config file
sudo cp -v /etc/modprobe.d/qemu-system-x86.conf{,~}
Open the qemu config file
sudo nano /etc/modprobe.d/qemu-system-x86.conf
Add the following line to the qemu config file
group=kvm
Add your user account to kvm group
sudo usermod -a -G kvm your_account_name
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