How to fix CompilerResultsLog: ERROR: A conflicting instance of UnrealBuildTool is already running

When I pressed build in visual studio, this error message came up and I don’t know how to fix it.

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I fixed the error by changing the solution configuration in visual studio from development editor to development.

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Restart PC, Mac Laptop.

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Find and kill dotnet.exe in your task manager process details list.

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For me this seems to be some kind of concurrency issue with the UE build system from the editor. For me it happens randomly when packaging a plugin. Just re-running the command a second or third time does the trick. This still happens in UE 5.4.1 and has since at least UE 5.2.1