While my computer is being repaired, I'm currently using my Grandmothers PC. She has Windows Vista, not sure if its 32 bit or 64 bit. But I have some pdf ebooks I was reading. At first, it was working fine, now suddenly, Adobe Reader X, whenever I open it, it closes immediately afterwards. I have searched the forums and it appears that no one else is having this problem. Does anyone know what may be causing the program to not stay open?