root@silver:~# apt-get install virt-manager libvirt-bin kvm
Reading package lists... Done
Building dependency tree
Reading state information... Done
virt-manager is already the newest version.
libvirt-bin is already the newest version.
kvm is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
After this operation, 0B of additional disk space will be used.
Setting up libvirt-bin (0.4.4-3ubuntu3) ...
addgroup: The group `libvirtd' already exists as a system group. Exiting.
* Starting libvirt management daemon libvirtd [ OK ]
After reboot I was able to install libvirtd
root@silver:~# apt-get install virt-manager libvirt-bin kvm
Reading package lists... Done
Building dependency tree
Reading state information... Done
virt-manager is already the newest version.
libvirt-bin is already the newest version.
kvm is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
After this operation, 0B of additional disk space will be used.
Setting up libvirt-bin (0.4.4-3ubuntu3) ...
addgroup: The group `libvirtd' already exists as a system group. Exiting.
* Starting libvirt management daemon libvirtd [ OK ]