OSX - Building lighting stuck at 0%

Having trouble building lighting on OSX, no matter what I try it gets stuck at ‘Building lighting 0%’. From some searching the common suggestion seemed to be it’s an issue related to the OSX firewall, however I’ve got mine disabled. I can see the UnrealLightmass process get created but nothing happens. Anyone else had this issue? Are there any log files created which might point to the problem?

Hi YazyBones,

Can you post this on the **AnswerHub**in the ‘Bugs’ section, if you have not already? This will allow us to track and address issues like this much more quickly.

If you have posted on AnswerHub can you link that here for others who may also have the same issue?

Thank you!


I have the same problem on Windows 7 64 every time when i first start the editor.After restarting the editor everything is fine but is really annoying.

Hi Tim,

There’s already an issue regarding this posted on Answerhub (Lighting freezes during build at 0% on Mac OS X. - UE4 AnswerHub) so I’ve added a comment to that rather than starting another one.