Ubuntu 13.04 all apt-get mirrors down [duplicate]

Apparently I can't get apt-get, as well as the ubuntu software centre, connect to any repository. I also tried to look for a suitable mirror using the ubuntu software centre (software sources->ubuntu software->download from->other->select best server), but it says it can't find any. My internet connection is OK (I'm writing here using the same pc on the same ubuntu), and there is no proxy.

Any ideas about what's going on?

Solution 1:

13.04 has reached EOL there for the repositories have been removed so there will be no more updates for 13.04 not even security so it is vulnerable to attacks.

There is an archive here that you can use to install software but it will be old software outdated and there will be no improvements and no new security update.

If you want to use an outdated release then edit:

/etc/apt/sources.list and change `archive.ubuntu.com to old-releases.ubuntu.com`

By:

sudo sed -i -e 's/archive.ubuntu.com\|security.ubuntu.com/old-releases.ubuntu.com/g' /etc/apt/sources.list

I recommend upgrading.