Unreal Engine 5 C++ Error MSB3073.

UnrealBuildTool : error : Unable to build while Live Coding is active. Exit the editor and game, or press Ctrl+Alt+F11 if iterating on code in the editor or game
2>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Microsoft\VC\v170\Microsoft.MakeFile.Targets(44,5): error MSB3073: The command “D:\Programs\UE_5.0\Engine\Build\BatchFiles\Build.bat SelfguidedMissilesEditor Win64 Development -Project=“E:\FILES\UnrealEngine\UnrealEngine5\SelfguidedMissiles\SelfguidedMissiles.uproject” -WaitMutex -FromMsBuild” exited with code 6.
2>Done building project “SelfguidedMissiles.vcxproj” – FAILED.

You solved this? I have the same issue

I have the same issue, and i built the solution from rider

Read the error.

You can disable Live Coding in the UE editor.

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Thanks, using Ctrl + Alt + F11 instead of Ctrl + Shift + B was the way to go for me. It was not clear that standard compilation and live coding were not compatbile…

In my case, the error message was not mentioning Live Coding:
Error MSB3073 The command ""C:\Program Files\Epic Games\UE_5.1\Engine\Build\BatchFiles\Build.bat" VSTesterEditor Win64 Development -Project="C:\Users\frank\Documents\Unreal Projects\VSTester\VSTester.uproject" -WaitMutex -FromMsBuild" exited with code 6. VSTester C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Microsoft\VC\v170\Microsoft.MakeFile.Targets

i have the same erro how did you solve it? im tring to build using Development Server in VS 2022

In my case:

  • if you want to keep “Live Coding” enabled, close unreal and wait 1/2 seconds before pressing CTRL+B;
  • disable “Live Coding” in editor preferences, close/open the editor if you’re not certain it worked, then CTRL+B in VS will works and trigger a hot-reload of the dll.

I’m not certain it solves your issue about Dev. Server, but i hope it help :slight_smile:

I did what you suggested and nothing works I made one created by me and one with lyra following documentation if you can or have another way I thank you very much

this is my case

This is my case Severity Code Description Project File Line Status deleted
Error MSB3073 The command “E:\UnrealLibrary\UE_5.2\Engine\Build\BatchFiles\Build.bat LyraServer Win64 Development -Project=“E:\Unreal Projects\LyraStarterGame\LyraStarterGame.uproject” -WaitMutex -FromMsBuild” exited with the code 6. LyraStarterGame C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Microsoft\VC\v170\Microsoft.MakeFile.Targets 44

i build my own following the documentation i had the same error