Hello Dkm Tracker, Next time you have a question you should post it on the Silent Hunter 4 General Discussion forum. There is a good group of people there and willing to help in anyway. What version is your game right now? To see what version you have, when you are at the main menu screen look to the bottom right and the version will be there. So you have Silent Hunter Wolves of the Pacific and you then got the add-on U-boat missions and you are trying to install that ?