# Lightmass crashes every build

**URL:** <https://forums.unrealengine.com/t/lightmass-crashes-every-build/342315>\
**Category:** Rendering\
**Tags:** Lightmass, UE4-10, build, unreal-engine, crash, question\
**Created:** [December 23, 2015, 11:21pm UTC](https://forums.unrealengine.com/t/lightmass-crashes-every-build/342315 "2015-12-23T23:21:01Z")\
**Posts on this page:** 1\
**Showing post:** 4

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**Author:** ![Tim\_Hobson](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Tim\_Hobson](https://forums.unrealengine.com/u/Tim_Hobson)\
**Post date:** [December 28, 2015, 4:11pm UTC](https://forums.unrealengine.com/t/lightmass-crashes-every-build/342315/4 "2015-12-28T16:11:06Z")

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Can you try the steps in the guide below and change the log verbosity to **Super Verbose**

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Once you build and get the error can you copy and paste the log into a text file and upload here? Maybe there is something in this that I can see that may point to the issue.

Also, were you able to Clean and Validate your cache? You had mentioned in the original post that you couldn’t open from your task manager and no mention in your last post.

It may also be helpful to get your DxDiag, so if you could attach that text file here as well I would appreciate it.

Thank you!

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