Hey there @Dr_Brinkmann! Does this apply to all projects? I noticed you mentioned it occurs in multiple versions. It’s basically reporting that the array (likely inside the mesh description of a mesh object) isn’t the size it was expected and something tried to access outside of it’s actual range. A few times running across similar errors, there’s been one mesh that was corrupted in one way or another. Do you have any form of source control? Does this still occur on previous project versions?