# Waitmutex exited with code 6 (MSB3037) **URL:** \ **Category:** C++\ **Tags:** UProperty, unreal-engine, Visual-Studio, CPP, question\ **Created:** [January 12, 2021, 12:58am UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119 "2021-01-12T00:58:47Z")\ **Posts on this page:** 10\ **Page:** 2
**Author:** ![Ebrahim.MR](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/ebrahim.mr/32/1220185_2.png) [@Ebrahim.MR](https://forums.unrealengine.com/u/Ebrahim.MR)\ **Post date:** [October 29, 2023, 9:36am UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/21 "2023-10-29T09:36:03Z")
for me it was I deleted a plugin from the engine and using it in my project ---
**Author:** ![jahtiainen](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/jahtiainen/32/738524_2.png) [@jahtiainen](https://forums.unrealengine.com/u/jahtiainen)\ **Post date:** [November 16, 2023, 2:45pm UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/22 "2023-11-16T14:45:47Z")
For me it was trying to build it in Visual Studio instead using the Live Coding way, Ctrl+Alt+F11 ---
**Author:** ![klobodnf](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@klobodnf](https://forums.unrealengine.com/u/klobodnf)\ **Post date:** [December 5, 2023, 5:21am UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/23 "2023-12-05T05:21:18Z")
If you had opened Unreal Editor Plz Close And Try Again Maybe Work. ---
**Author:** ![102567](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@102567](https://forums.unrealengine.com/u/102567)\ **Post date:** [February 16, 2024, 2:34pm UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/24 "2024-02-16T14:34:47Z")
I have a same problem. Do you resolve this error??? ---
**Author:** ![sirEiven](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/sireiven/32/1100032_2.png) [@sirEiven](https://forums.unrealengine.com/u/sirEiven)\ **Post date:** [April 21, 2024, 11:05pm UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/25 "2024-04-21T23:05:17Z")
I found out that in my case it was related to a plugin “AccuRig”. When it is activated it generates this error. I deactivated the Plugin and now ue / Lyra is working. Change in LyraStarterGame.uproject the following lines: ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/0/7/7/077a8b23862c91d1c18178a29b6a2de6281947a4.png) from True to false. This resolved my issue, maybe your issue is related to same plugin or other. Check LyraStarterGame.ueproject which plugin are activated /deactivated. I would deactivate all thirdparty plugins. Hope it solves for you, kind regards, Ivan ---
**Author:** ![Maxwell\_Noodle](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Maxwell\_Noodle](https://forums.unrealengine.com/u/Maxwell_Noodle)\ **Post date:** [April 24, 2024, 1:24pm UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/26 "2024-04-24T13:24:33Z")
Hey I know its been a year but im following the same tutorial you are and have the same error, did you ever find a fix? ---
**Author:** ![Adity\_TM](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Adity\_TM](https://forums.unrealengine.com/u/Adity_TM)\ **Post date:** [May 20, 2024, 1:55pm UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/27 "2024-05-20T13:55:27Z")
Close all the running instance of Unreal, search in task manager if any instance is running and close it then go to visual studio and build the project. ---
**Author:** ![SunnyPixel](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/sunnypixel/32/921017_2.png) [@SunnyPixel](https://forums.unrealengine.com/u/SunnyPixel)\ **Post date:** [October 23, 2024, 4:37pm UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/28 "2024-10-23T16:37:14Z")
Try using cmd prompt to see more details about the error ### **Run Build.bat Manually** You can manually run the command to gain more information about the error: 1. Open a Command Prompt. 2. Run the command from the error message: 3. “E:\Program Files (x86)\UE\_5.3\Engine\Build\BatchFiles\Build.bat” Vr\_Game\_CPPEditor Win64 Development -Project=“G:\Game\_CPP\Game\_CPP.uproject” -WaitMutex -FromMsBuild 4. See what the error says, it can be a misspelling or something else. ---
**Author:** ![Mad.King](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/mad.king/32/761302_2.png) [@Mad.King](https://forums.unrealengine.com/u/Mad.King)\ **Post date:** [October 26, 2024, 4:31pm UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/29 "2024-10-26T16:31:56Z")
Thanks, this helped me pin down what was causing my build to fail with this error. Upgrading a project from 4.27 to 5.3, one of my lines was using Hit.Actor, where Hit.GetActor() is now needed instead. I wouldn’t have guessed that running the .bat manually would offer more context. Rather annoying that it gives such a vague error in the first place. ---
**Author:** ![D3fault888](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@D3fault888](https://forums.unrealengine.com/u/D3fault888)\ **Post date:** [June 21, 2025, 10:46am UTC](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119/30 "2025-06-21T10:46:52Z")
I had the same error. the line just above it said “unable to build with live editor running”. I closed live editor (Unreal Engine) and looked in task manager as well to ensure its closed. Build completed successfully after that. [Previous page](https://forums.unrealengine.com/t/waitmutex-exited-with-code-6-msb3037/477119.md?page=1)