Hey, I would verify your game cache firstly if the game isn't starting up. Secondly install a third party program designed for finding faulty mods for skyrim. Loot, similar to Boss, is what I use and it can be found here https://loot.github.io/. It's a great program and helped me a lot but time to time, I still have in-game crashes while it detects no errors. Wyre bash can be manually installed from here http://www.nexusmods.com/skyrim/mods/1840/?. It's handy, highlights bad saves or mods in yellow or red I believe. This is optional but helps clean your mods and all & all just makes for a cleaner, safer modded skyrim. Tes5edit: http://www.nexusmods.com/skyrim/mods/25859/? This guy "Gopher" goes through it thoroughly on cleaning your master files. I cleaned all the dirty mods loot warned me about just as I did my master files. If you verify your cache or reinstall skyrim, it resets them and they will need a cleaning again, so reinstall first if you think you might have to. https://www.youtube.com/watch?v=fw3g_N1jcZQ