How do fix the error "could not be compiled. Try rebuilding from the source manually"

Hello everyone, IM doing an Unreal Engine 4 tutorial series and I’m instructed to open their game but whenever I open it, I get the error of “BullCowGame could not be compiled. Try rebuilding from the source manually.” What do I do to fix this? This was made with Unreal Engine 4.22 so that might be the problem but I don’t know.

Thank You,

Yours Sincerely, Olezka06.

I am having the same problem with a project that I want to upgrade from UE 5 preview2 to UE 5 release.

And I don’t know how to “Rebuild manually” the project to update it to the new version of UE 5.

Can anybody help me?
Greetings and thanks in advance


facing the same issue, if anyone knows about this, kindly help. thank you

So, What you wanna do is open the solution file (.sln) if it’s not there then first right click on your ProjectName.uproject and generate visual studio files.

Here my project name is GoogleTTS yours might be different

once the .sln appears open it using visual studio or Rider then press ctrl+shift+B in your case it will throw some errors and those are the cause of problem most likely.

Post the errors.

*Info for the people who don’t know how to rebuild (have never done it before):
You need Visual Studio Community (not Code). After its installation you will most likely run into the next error, which seems to be common with UE5:

A fatal error occurred. The required library hostfxr.dll could not be found.

If so, continue following this info to install the right version of .NET Core:

After that you should be able to rebuild just fine in VS.

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