Doors (Missing 3D Display)

AECOsim Building Designer V8i (SS4)

Version 08.11.09.563

Projectwise Explorer V8i (SS4)

Version 08.11.11.115

Hi all,

all of a sudden, doors in my design file don't show their 3D forms anymore but only the 2D annotation cells are showing . can someone please tell me how to resolve this   

I welcome any suggestions

thank you

regards