I work at Iowa State on a fairly large Unity game. It is currently built with Unity 4 and my job is to update it to work with Unity 5 (specifically 5.4.1).
I can open the game in Unity 5 and run a few scenes with no serious problems. However, some scenes will open and let me explore in the Scene tab but when I press play it crashes Unity completely. Any Ideas on what the problem is and how to fix it?
I’ve had similar issues in the past after upgrading that I could not figure out what is causing the crash. If possible for your project, disable groups of gameobjects in your scene that is crashing until it runs, and narrow it down that way. You should be able to determine what asset / plugin / script is causing the problem just by seeing when it runs and when it doesn’t with various gameobjects disabled.
Figured out that if I open almost any script and edit it in any way, save it, and recompile it in Unity then the scene will actually let me play the scene without Unity crashing. Also when I recompiled all the scripts they started to spit out a ton Warnings. I fixed a bunch of them and Unity keeps running smoother and smoother. Thanks to everyone for your help!