am working on a corporate intranet and  drupal has proved to be very useful so  far,  i have been looking at the diffeent modules available but i cant seem to find one
that will handle documents easily ( upload, view and share  word, PDF Excel etc,  on different user roles, just like KnowledgeTree

My question is, does such a module exist? and if not, is there a way to intergrate KnowledgeTree into drupal such that a user has to sign in only once?


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David Njuki.