Graphics kernel error: 0xfffffffd

[MarjoleinPeters1]

Graphics kernel error: 0xfffffffd

Suddenly.

I played the game many times this week on different days without any problem.

And yet, today, it keeps crashing when loading / entering my city. 

"Graphics kernel error: 0xfffffffd"

Why? I did not change anything on my mac. 

Game was running very smooth.

Please help?