For the past week, whenever I try to update via the Update Manager, I get the following errors:
Here is the screenshot:
[W:Failed to fetch http://ppa.launchpad.net/pmcenery/ppa/ubuntu/dists/precise/main/source/Sources 404 Not Found
, W:Failed to fetch http://ppa.launchpad.net/pmcenery/ppa/ubuntu/dists/precise/main/binary-i386/Packages 404 Not Found
, E:Some index files failed to download. They have been ignored, or old ones used instead.
My internet connection works perfectly as I am able to access this forum. I don't understand the sources of these errors since I am still learning to use Ubuntu. Please help me out with this error. Thanks in advance for your help.