I faced same problem with 1 mod, when re-installing mods after installing clear version of Skyrim (and it says "Mods are installed" but it's clear game without mods :D) and that problem was with Avast. He show notifications about "This file is trying to access to delete file ****.jpg" i just click like forget about it, Avast and mod will succesfully re-install :3 I appology for possible illiteracy