So I have been trying to build my class project so I could take a video of it and the light transport is stuck at 7/11 Light Transport - 1 Job and has been that way since 2:00AM. Now here we are 7 hours later… The editor is not frozen just the build. This happened before but I just cancelled the build. Current Version 5.1, but also happened with the previous version.
Hello LT, I understand you are having issues with the illumination system in Unity 5.1. I have been struggling with the same issue when I ported our projects to the new Unity 5.1. The issue was later resolved when we decided to uncheck the “Static” radio button on all scene objects. It could be some Graphics Device issue with Unity, or perhaps our scene was too complex with too many draw calls. Either way, if that does not help, try lowering the graphics settings in the “Lighting” Panel to a lower resolution or try disabling “Baked GI” in Lighting > Scene > Baked GI.
Cheers!
Joshua Buist @ Electric Fountain
I am having same problem…it gets stuck on 7/11 Light Transport, I am using 5.1.2f1 personal.
Verified that the build does not get stuck if you toggle everything to non-static,
but when there is no static objects it does not build anything.
i then started to set needed objects to static. I hit a offender but I cant figure out why. I wrote a bug.
Had a similar issue in my space scene getting stuck on 7/11 Light Transport when I added a large space station. I noted that if I scaled the station down the job didn’t stick.
This is workable for us as we use a ‘space’ scale anyway to deal with float size limitations …, distances and sizes are just to big for 1 = 1m so we have scaled space by 0.01 for our purposes and that seems to do the trick.
Removing baked GI made it go from taking between 5 minutes and not finishing to being done in less than a second for me.
iam stuck at same place with unity 5.5.1f1
found this post:
https://forum.unity3d.com/threads/light-transport-problem-with-large-objects.310405/
best, pascal
Hi!
This problem appears because you use Navigation and Bake in your map, you need setting Step Height for Navigation, anyway helped me.
You may not have enough space on your primary hard drive, or the one you actually have unity installed on, as it seems to need some temporary data.
despite the fact the scene I was working on was on a separate hard drive, I was able to continue baking after I cleared up some space on my hard drive that unity was installed on.
to fix this issue,just make sure no objects are set to static and if you are using navigation and need to make an object static then -select the object go to navigation tab then go to objects and tick “navigation static”.hope it helps
Hello there ; I had the same problem. I found a solution like this.
Select any object from the scene. When your object is selected;
Select the “Lightmap Static” segment from the “Inspector” panel.
Then ; (Window> Lighting> Setting)
In the opened panel;
Select “Ambient Mode” (Bake)
Wait until the cooking process is complete in the lower right corner of the Unity window. (7/11 Light Shipping - 1 Business)
Then you can get built.
You should also apply it in all scenes.
Good luck 
Hmm…I have the same issue after selecting a lot of objects as “static” - however I did that on purpose, exactly because these are static = never moves.
As I understand lightbaking, for all static object, Unity can bake light, to make it much easier to run on the client/players machine later - better performance.
So, I’m wondering why all the “fixes” in here, is about just turning static off or unchecking “Baked Global Illumination” - isn’t the reason this works, because you are then basically not baking any lightmaps - meaning yes, the “generate lightmaps” is done fast - but you didn’t get any lightmaps, so you really didn’t gained anything either?
Or am I missing something?
I found it was specifically caused by having some background mountains (from an ANGRY MESH pack) set to static. It had no collider and had ‘contribute to global illumination’ unchecked.
Since they were not supposed to contribute to the lightmap anyway, I turned static off for them and it fixed the issue. However, its still not a great way to deal with it.