Thanks for your reply and first of all, happy new year ??
In fact, the first time i check the theme an had the notifiction to install for improving experience, i installed slidedeck then insite without problem, an then it appears with the installation of Responsive Ad-on, the first one.
The problem is i can’t download it separatly on wordpress because it shows me the same error in repos.
So i tried to deactivate the others an retry install, same thing.
I would like to download it separatly an upload it by ftp, but no link.