If you are running an older version of the simulation, this update is a must-have . Just be sure to back up your save files before applying it, as version jumps can sometimes cause neighborhood corruption.
, ensure they are updated to the exact same version as your game update (e.g., 1.67 or 1.69). Could you clarify the specific version number (e.g., 1.67) or Expansion Pack you're trying to update? rldsim3iso upd