My bet is on either SMIM or XPMSE . I have had many repeatable CTDS in the past in both Classic and SE that were definitely caused by at one or the other of those two . I would also not rule out FNIS , I ' ve never had a good experience with it in Classic even when I did everything just right . Start by removing SMIM and any SMIM compatibility patches you have in , and see if it still happens . If it does , deactivate XPMSE and try again . And just want to say , I ' m not bashing or saying that any of these are bad mods . Just that , in my own experience , they have definitely been the culprits of repeatable crashes and that I have experience much fewer CTDS since I stopped using them . Many other people swear by them , so YMMV .