I know this post is a bit old and I got a link here from another forum, but I'd just like to say thank you to everyone on this topic, especially the OP. I had uninstalled all of my mods and was still getting CTD every time I built anything in Sanctuary. I didn't realize I still had residual files left from mods I had tried and didn't like. Still verifying the file integrity, but I think this will solve my problems. It was ticking me off, though, since I have a decent PC. (Intel i7 3.4GHz 16GB DDR3 4TB HDD 1000W PSU Nvidia GTX 970) Again, thank you so much.