Virt-Manager is not working in Mnajaro 21.1.0 Pahvo

[Shirshendu]

@Zilch510

su: Authentication failure

That’s wanting your root password, not user password. Did you set a different root password other than user password during installation of Manjaro?
In case you forgot the root password somehow,

Change root password

Do this: sudo su type password of your user and check if you are root: whoami Then type: passwd type your new root password <enter>