I will preface with what I have tried, I have tried redownloading the the minecraft jar and the entire .minecraft folder. I have also tried redownloading and extracting the modpack. Whenever I attempt to use the bat installer the command prompt will flash onscreen and then vanish. Puzzled as to why I am having this issue, and am wondering if it could be connected to my having my windows 7 Os on an SSD separate from the rest of my files. Also when extracting the files it keeps asking whether I want to copy the folder without encryption.