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I have been having trouble with this. My computer in Ubuntu Linux and I know it's Ubuntu 13.0 something or higher. I've tried installing flash player and it gives me this error message "There isn’t a software package called “adobe-flashplugin” in your current software sources." I tried doing what I saw one person say online and download something called "pepperflashplugin-nonfree", and it is still giving me the same error message! Please help me!