Re: Can't Change Sim Lifespan

@msphoenixnoire  Try changing the value manually.  Go into Documents > Electronic Arts > The Sims 3, open options.ini, and search for aginginterval .  Set it to 3.  The values are 1 to 4, Short to Epic, in order.

You can manually change the length of any age stage as well.  There's one value per stage, all starting with agingstagelength .

It is strange though that the option is grayed out.  I'd actually delete the current options.ini and let the game create a new one, then see whether you can change the age length.  If not, the file itself is probably being protected by an antivirus, or perhaps cloud syncing that's hung up for some reason.  It could also be mod-related, although I don't know of a specific mod that would do that.  Still, try removing your mods, if you have any, and see whether it helps.