To discover which version of SH4 you have, go to the game's root folder, which in a near-default install would be "Ubisoft / Silent Hunter Wolves of the Pacific". Right-click on the "SH4.exe" file. If you do not have "show file extensions" turned on, then it is the first "SH4" in the list. Then in that context menu, left-click on the "Properties" choice. That will open a Windows Dialog. Left-click on the "Details" tab, and in the middle of that page should be a "Product Version" listing.
