UE 5.6 project creation fails on Default.rc2 / rc.exe — exit code -1

Hey folks,

I’m running into a blocking issue when creating a new C++ project in Unreal Engine 5.6.
The project fails to compile during creation (at about 2% progress) with the following error:

[1/48] Resource Default.rc2  
Resource Default.rc2: Exited with error code -1. The build will fail.  
rc.exe command:  
.../Windows Kits/10/bin/10.0.22621.0/x64/rc.exe ... "../Build/Windows/Resources/Default.rc2"

Then it ends with:

Result: Failed (OtherCompilationError)

Some key details:

  • The failure happens during project creation, not after — specifically during the initial compilation step.
  • I’m on Windows 11 with Visual Studio 2022 (v14.38.33145) and Windows SDK 10.0.22621.0
  • I’ve completely uninstalled and reinstalled Visual Studio, manually cleaned registry leftovers, and reinstalled the full C++ toolchain, MSBuild, and SDKs
  • I also fully reinstalled Unreal Engine 5.6
  • I manually tested both rc.exe and cl.exe — they run fine from the command line
  • Environment variables look fine, system-wide PATH and INCLUDE are set correctly
  • C++ projects won’t build or open at all — even existing ones fail
  • Only Blueprint-based projects work fine

Tried:

  • Running UE and VS as admin
  • Rechecking Windows Kits path and permissions
  • Verifying engine installation
  • Rebuilding project files manually from .uproject
    Still no luck.

Would really appreciate any help or ideas — this has been driving me nuts!

Thanks in advance!

You can try forcing your SDK version in your buildconfiguration xml file

Your project path\Saved\UnrealBuildTool\BuildConfiguration.xml

<?xml version="1.0" encoding="utf-8" ?>
<Configuration xmlns="https://www.unrealengine.com/BuildConfiguration">
   <WindowsPlatform>
<WindowsSdkVersion>10.0.22621.0</WindowsSdkVersion>
</WindowsPlatform>
</Configuration>

5.6 compiles ok on vs 2022 (v17.14.5)

<?xml version="1.0" encoding="utf-8" ?>

<Configuration xmlns="https://www.unrealengine.com/BuildConfiguration">
	<BuildConfiguration>
		<bAllowUBAExecutor>false</bAllowUBAExecutor>
	</BuildConfiguration>
</Configuration>

This also works locally in my case, but now I can’t use RiderLink’s Engine installation default. This means I need to install it for each project using 5.6.

Why did UBA just break the defaults? I can’t answer that, but these are the workarounds.

EDIT:
You want this snippet in two locations (Windows paths):

  1. <PROJECT_DIR>\Saved\UnrealBuildTool\BuildConfiguration.xml
  2. %APPDATA%\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml

That resolves issues for now by turning off UBA and using your local MSBuild.exe. It can be modified to use clang or intel as well.

1 Like

This is almost the same issue — my rc.exe was taking a very long time and sometimes even getting stuck.

In my case, the fix worked by editing <PROJECT_DIR>\Saved\UnrealBuildTool\BuildConfiguration.xml

<?xml version="1.0" encoding="utf-8" ?>
<Configuration xmlns="https://www.unrealengine.com/BuildConfiguration">
    <BuildConfiguration>
        <bAllowUBAExecutor>false</bAllowUBAExecutor>
    </BuildConfiguration>
</Configuration>

By the way, I also tried modifying only the WindowsSdkVersion, but it didn’t work:

<WindowsPlatform>
    <WindowsSdkVersion>10.0.22621.0</WindowsSdkVersion>
</WindowsPlatform>

I also tested adding the config to
%APPDATA%\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml,
but that didn’t work either. It seems UE5 may be using some cached configuration.

Thx to everyone above for the helpful replies.

Hello guys, i may have found the problem, i had no issues building my projet and since i have changed my game icon (projet setting > plateforms > windows) i got this exact line :

Resource Default.rc2: Exited with error code -1. The build will fail.  
rc.exe command: ....

so apparently UE accepts icon only in:

256x256
64x64
48x48
40x40
32x32
24x24
16x16

but guess what its has to be a specific format “.ico“ and you can not fool the system by just changing the extension by rename it, i wasted time thinking it will work and it did not, i had to export my game logo with GIMP:

-import your Png
-set scale by 256x256
-file > export by
-select a file type > search for and select "Icon Microsoft windows" > export
*-and if it ask you, select "32bpp, 8bit alpha, no palette" and check compressed PNG

and it work just fine for me, but i believe using an icon converter or some other app with this .ico export features can also work, in my case i only did it in 256x256 and i dont really know if the others works.

I had hours of searching,visual studio uninstall/install and goofing around only to find out it was an icon format issues.

i hope it solve ur issue, Have fun !!