Welcome to LQ.
Ubuntu 11.10 : The release version of 'apt' works OK.
? May be you updated apt to an unstable version ?
Apt can also fail when you run it from a directory that doesn't exist.
Solutions : May be the package list is already updated.
Then continue to the next step, like :
sudo apt-get install \
g++ make autoconf automake make libtool libxmu-dev patch xgraph
If it's not working either, then install the few packages with
the 'Muon Package Manager' or 'Muon Software Center'.
Muon* can also be used to install 'synaptic'.
The 'synaptic' package manager has a 'Refresh' button,
which does the "package list update" like 'sudo apt-get update'.
Last edited by knudfl; 05-07-2012 at 01:04 AM.