SHADERS AND LIGHTS GONE!!!!

[leonardo_galli5]

Hi, quick question

im rendering my model and everytime i save and exit from alias the shaders and lights are gone. everytime i open my model and i go to my shaders its empty and i lose every progress i make and i have to do everything back from the start… how can i solve this problem please HELP ME EXAM IS IN 2 DAYS

[Fausto_Brevi]

Did you use File->Open or File->Import->File?

By default, File->Import->File doesn't load shaders and lights, but only geometries and layers. 

Anyway, I suggest you to check the option panel and verify if shaders and lights are marked for being kept.