• It is important to have the system updated with the latest patches, security fixes and package upgrades from the repositories.

• Ensure that the correct repositories are enabled by going to 

               System --> Administration --> Software Sources

• Then open the command-line terminal:

               Applications --> Accessories --> Terminal

• Update the repositories by typing the following command

               sudo apt-get update

                               (The system will ask for your user password.)

• Upgrade the packages of the currently installed version:

                sudo apt-get upgrade

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