I'm already working on project a month. I'm building parts, and then mate them in assembly. Yesterday, suddenly when save project, close SolidWorks, and open again, all sketched CONSTRUCTION LINES are disappear from normal view/mode.
I have test program to create new part >> open a sketch >> create some construction lines >> exit sketch >> and lines are normal viewed.
I think project file has crashed, or a bug appears. I'm mean it can be stressful after so many hours of work.