Yes you need DirectX v9.0c installed. It has certain files in its Library that the game needs. Microsoft will not let it overwrite your DirectX v11, but it will add the necessary files in. THEBERBSTER has a link to the MS site for it in his
... TUTORIALS <> HOW TO DO IT <> INFO ... thread. Look below his section header "Download, Post Links & Information For SH4". Don't worry about the "SH4" naming. DirectX v9.0c applies to all of the Silent Hunter games...