When I tried to install ia32-libs on Ubuntu 15.04 it gives me this error:
N: Ignoring file 'ia32-libs-raring.list' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
N: Ignoring file 'ia32-libs-raring.list' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
E: Package 'ia32-libs' has no installation candidate
Run the command:
sudo rm -f /etc/apt/sources.list.d/ia32-libs-raring.list
That will clear the first two errors. As for installing ia32-libs, that package has been deprecated for a while now. Whatever instructions you are following are outdated. For more information see What happened to the ia32-libs package?
Also, please upgrade to Ubuntu 15.10, 15.04 will become end of life next month. You will lose updates and support and upgrading will become harder.
