Only thing that comes to mind is for you to use the "verify" function in Galaxy to verify the game files are all there and in the proper version, and then if that doesn't work you should try uninstalling and then reinstalling the game through Galaxy. If you still get nowhere, then try downloading the manual install files and then installing the game from them (you should be downloading all of your games manually in order to keep installable copies of them, whether you use Galaxy, or not, imo--It's what I do.) So you have a couple of options to try.

If after all is said and done you still have this problem then I suggest that some program or utility you are running in your Win7 installation is interfering with the game, somehow (I'm assuming Win7 x64 SPI is what you are running.) With older games and older OSes like Win7, this could sometimes happen every now and then. At any rate the game runs flawlessly for me in Win10x64--so at least you will know it does run as it's supposed to if the environment is right...;)