After upgrading from Ubuntu 16.04 LTS to Ubuntu 18.04 LTS, I can no more start Virtual Machine Manager. It was running okay when I was using Ubuntu 16.04 and I didn't face any problems but after the upgrade, everything broke. I even installed Windows 10 on it. Running it from the Applications Launcher just don't show anything. I tried running it from the terminal but I always get this error:

/usr/bin/virt-manager: 3: exec: /usr/share/virt-manager/virt-manager: not found

I tried several times on the terminal but it always throw that same error message, which I don't seem to understand. I thought KVM wasn't installed but running kvm-ok gives the following message that KVM is installed and acceleration can be used:

% kvm-ok           
INFO: /dev/kvm exists
KVM acceleration can be used

Also, the Windows 10 image file still exists in /var/lib/libvirt/images, plus other directories in the images parent directory.

How can I do to make Virtual Machine Manager run again.

  • 1
    apt install --reinstall virt-manager – Ipor Sircer Sep 9 '18 at 21:06
  • Running sudo apt install --reinstall virt-manager gives: /var/lib/dpkg/info/virt-manager.prerm: 6: /var/lib/dpkg/info/virt-manager.prerm: pyclean: not found new virt-manager package pre-removal script subprocess returned error exit status 127 Errors were encountered while processing: /var/cache/apt/archives/virt-manager_1%3a1.5.1-0ubuntu1_all.deb E: Sub-process /usr/bin/dpkg returned an error code (1) – Nayi Sep 9 '18 at 21:18

You said the error was, in relevant part:

pyclean: not found

pyclean was provided by python-minimal package, so you should reinstall that first.


Same issue here, found issue was caused by a python library update after installing awscli. I was forced to restart my system and tried opneing virt-manager and could not open it via GUI, wne to cli and ran:

sudo virt-manager


/usr/lib/python2.7/dist-packages/requests/__init__.py:80: RequestsDependencyWarning: urllib3 (1.24.1) or chardet (3.0.4) doesn't match a supported version!

A Google search found this thread on github: https://github.com/requests/requests/issues/4673. They were all discussing about the urllib3 (1.23.1) breaking a bunch of apps including awscli; which I had just installed 2 days prior. At the end of a thread one of the users explained that he back reved the library to version 1.22 and installed awscli again which fixed his problem. Command:

pip install --upgrade "urllib3==1.22" awscli awsebcli

Welp monkey see it works, monkey follow and it fixed my issue with Virt-Manager, tested awscli and it still works so.

TLDR: if you installed awscli and now Virt-manager broken run

pip install --upgrade "urllib3==1.22" awscli awsebcli

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