I should say that I was helping my fiancee set up a few mods I had that she liked, and her NMM allows FO4 mod installation without any problems. Clean install of NMM. The only obvious differences between our rigs: She is running Fallout from her large HDD, as her SSD is almost full. She is running Win 8.1 Pro x64, whereas I am running Win10 Pro. I can manually install mods and add them to the plugin list just fine, but again, NMM refuses to accept that my .ini's are in order.