Sims 3 late night out expansion pack

[littlesims3helpinggirl]

Hello, my sims 3 world latenight out says my sims 3 base game is incompadble with the current sims 3 expansion pack and it says please update your game via the game laughcher what does it mean by that sincerly brye coles

 

[hang-the-9]

When you start Sims, it will tell you that a new update is available, run the update. You need to run patches to it or expansions won't work.