Hello Ben119, you also have Norton AV? .. if yes, then you need to find a way how to set FL/CF files to exceptions. Maybe can work if you set (if is possible) whole folders (Freelancer and FLMM) to exceptions, then shut down Norton and do clean installation for CF (How I install/reinstall this mod?) Problem here is Norton AV, not the operation system. I have installed CF 1.9 on 2 PCs with Win7 and both works smoothly (but I do not have Norton - fortunately)