Do you mean installing when you say uploading? And that the new item isn't visible in the Content palette? If so, and if you had previously been using 2.0 or earlier, this is probably just the usual issue that DS now defualts to the category 9database) view  -click on the triangle button at the extreme top-right of the Content palette and either do a search for new content (which should add it to the Unassigned folder) or select one of the View folders as... options.