I have a linux mint system 17.1 and I want to install postgresql.Now in trying to update the packages, I type: sudo apt-get update and here are the error messages I get:W: Unable to recover archive.canonical.com/ubuntu/dists/rebecca/partner/binary-amd64/Packages  404  Not Found [IP: 91.189.92.191 80]E: The download some index files failed, they have been ignored, or old were used instead.I am a beginner. Barely two months since I started using linux mint 17.1 Thank you for your answers!
Installation of postgresql on linux mint 17.1 (problem with apt-get update)
apt;repository;postgresql