I just installed elementary on my HP Pavilion, dual boot with the pre-installed Windows 10. I can't install anything, using either the app center or apt-get. Here's what is happening when I try to install firefox
anthony@anthony-HP-Pavilion-Notebook:~$ sudo apt-get install firefox [sudo] password for anthony: Reading package lists... Done Building dependency tree Reading state information... Done Package firefox is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source E: Package 'firefox' has no installation candidate
And when I use the app-center, it simply does nothing. Thank you in advance for your help.