Cannot complete system updates

Good morning

I get the following error message on Ubuntu Lucid Lynx after I try to run the updates.

Failed to fetch http://ppa.launchpad.net/nico/ppa/ubuntu/dists/lucid/main/binary-i386/Packages.gz 404 Not Found
Some index files failed to download, they have been ignored, or old ones used instead.

Then it puts a warning message on the right side of the upper task bar.

Is also says:

The repository may no longer be available or could not be contacted because of network problems. If available an older version of the failed index will be used. Otherwise the repository will be ignored. Check your network connection and ensure the repository address in the preferences is correct.

Is there a way to avoid this problem?

Regards,

Eric Nicholls