My game is completely up to date, as are all my mods. There's no problems with my laptop, and my game never crashes or bugs out (except for 'heavy save' issues). It's been a while since I played a vampire, and I did see that some people had trouble with their vampires automatically being immortal after patch 1.50/University. Unfortunately, none of those folks got their answers, and as for myself I have no idea if this is when my problem started-- I seriously haven't played a vampire since long before University.

To test it, I removed all my mods pertaining to SN occults. Went into the game, and sure enough my vamps were still immortal. They lost their immortality when I removed their vampire status, then made them vampires again.

Anybody have any clue as to why this is happening? It's not impossible to fix, but it sure is tedious, and I want my vampires to be mortal unless otherwise decided. Although it appears that I'm the first to ask on MTS, other people have had this problem too.

Any answers are greatly appreciated.

I think I read somewhere that adding SN makes vampires automatically immortal when they age up to YA. I can't really check it out personally though, so do take this with a pinch of salt.

Hopefully someone a bit more knowledgeable will come along soon.

Thanks for the answer! I've figured out a solution, at any rate. Here's hoping it sticks.

IIRC, I think I did the same and it didn't work. Could very well be wrong, but I wouldn't be surprised if they magically regained their immortality the next time you boot up the game. :/

Yeah, I'm hoping it won't. I just used StoryProgression to turn aging off and then back on again for them, and it forced them back to normal. It should still be that way, but I can always just do the same thing again.

Update: So far so good. I haven't had the revert to immortal yet, so I guess that's a good enough solution.