Waitmutex exited with code 6 (MSB3037)

So I was scripting, following a series when I ran into this problem. I know this error can be caused by UPROPERTY, but I have no idea what triggers this conflict. Here is my UPROPERTY code:

326982-help.png

(this is a header file)

Severity Code Description Project File Line Suppression State
Error MSB3073 The command “E:\UE_4.26\Engine\Build\BatchFiles\Build.bat FPSGameEditor Win64 Development -Project=“E:\StealthGame_ProjectBase_4.25\StealthGame\FPSGame.uproject” -WaitMutex -FromMsBuild” exited with code 6. FPSGame E:\Visual Studio stuff\MSBuild\Microsoft\VC\v160\Microsoft.MakeFile.Targets 46

Any help will be appreciated.
Thanks!

It says I’m using 4.26 in the dir, but I’m using a downloaded template that was made in 4.25.

Never mind. I spelt category wrong. For anyone else who has this error, check your UPROPERTY code for any misspelling.

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what i can do to fix that i don’t understand what you mean??

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how ??when build the project that happen what i should do to fix it??

You can fix this by recheck your code at the line you declared UPROPERTY you maybe misspelling
some word in that line wrong.

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You can explain more because i’m begineer in this track

Can I have the picture of your code please?

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When i open that project the photo is above is happen no code

On the right side of your picture above you’ll see ‘Source’ maybe click on that.

I don’t write any code

life saver!just a spelt sth wrong

I add the same problem and the problem for me was the fact I didn’t have closed unreal engine before launching the compile ( read the output log not the compile error list)

Hey guys! Im stuck with the same WaitMutex error… I checked spelling. Any further ideias. im stuck.

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It worked for me by choosing rebuild instead of built

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Had the same mutex error on a brand new project, the “close Unreal and Rebuild” method worked for me.
This was for a blueprint project where I added a C++ class to fix the Off World Live packaging issue.

Just updated from UE 5.1 to 5.1.1

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This error can trigger in multiple situations :hot_face:.

For example, it can be caused by a duplicate .cpp filename or by a typo or wrongly placed UPROPERTY macro.

I wonder if there is a way to make this error more informative for the user?

If this error is caused by a UPROPERTY (many causes are possible), I have found that Rebuilding the project can trigger an actually informative warning message to appear, but for duplicate filenames, there is no way to get more information about the underlying error.

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ye…@lovelacestudio your solvation worked for me … in visual-> games → your project name → right click and rebuild

This was also the answer for me.

I updated Visual Studio (Community Edition) and received this error during my next build.

Cleared Binaries/Intermediate folders and regenerated Visual Studio files and I still got the error.
A Rebuild Solution was what worked for me.

Close UE5 and rebuilt it

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