Cannot install module auto upgrade in PS 1.5.6.1

[3mp3ri0r]

Hi all, I really need all of your help. I've problem when I want to install 1-click upgrade. Currently I use prestashop 1.5.6.1 and want to upgrade to prestashop 1.6. When I click install button in module tab in back office, it tell me 2 errors. It was "Error on downloading the lastest version" and "Module not found". When I upload the module manually and want to install it, I still got the same errors. Why it can be like that and what should I do to install that modul?

Thank you.