ubuntu update issue

If your ubuntu is failing to update/install software, make sure you have the ubuntu update repository set in your apt source.list file:

###### Ubuntu Main Repos

deb http://us.archive.ubuntu.com/ubuntu/ lucid main restricted universe multiverse 

###### Ubuntu Update Repos

deb http://us.archive.ubuntu.com/ubuntu/ lucid-security main restricted universe multiverse 

deb http://us.archive.ubuntu.com/ubuntu/ lucid-updates main restricted universe multiverse