I don't particularly have a clue what happened, all I remember is that I was doing everything as usual and with these exact mods for at least a day with no issue and then I logged back on to the attached error message. As far as I know I don't believe i've goofed anything personally, like I never messed with the files or anything, and I didn't have any instances of the modded guns being either in my stash or inventory, neither do I believe i had any of modded clothes on at the time, if that helps
the gloob