cannot download from ubuntu software centre
 

im getting this error when i try to download form ubuntu software centre
The action would require the installation of packages from not authenticated sources.
please help

Welcome to LQ.
That happens all the time, when the Ubuntu version is about getting old.
... ( And the message can be ignored, is not an error.)

Which version are you using ? ?
This command will tell : $ cat /etc/issue <Enter>

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