Unable to build unreal engine from source (Nuget package issues?)

Development Getting Started & Setup
,
1

After downloading the source code, installing visual studio and required packages and running setup.bat and then trying to run GenerateProjectFiles.bat, I’m getting errors with nuget packages being incompatible with net6.0:

D:\UnrealEngine\Engine\Source\Programs\Shared\EpicGames.Serialization\EpicGames.Serialization.csproj : error NU1202: Pa
ckage OpenTracing 0.12.1 is not compatible with net6.0 (.NETCoreApp,Version=v6.0). Package OpenTracing 0.12.1 does not
support any target frameworks. [D:\UnrealEngine\Engine\Source\Programs\UnrealBuildTool\UnrealBuildTool.csproj]
D:\UnrealEngine\Engine\Source\Programs\Shared\EpicGames.IoHash\EpicGames.IoHash.csproj : error NU1202: Package OpenTrac
ing 0.12.1 is not compatible with net6.0 (.NETCoreApp,Version=v6.0). Package OpenTracing 0.12.1 does not support any ta
rget frameworks. [D:\UnrealEngine\Engine\Source\Programs\UnrealBuildTool\UnrealBuildTool.csproj]
D:\UnrealEngine\Engine\Source\Programs\Shared\EpicGames.Core\EpicGames.Core.csproj : error NU1202: Package OpenTracing
0.12.1 is not compatible with net6.0 (.NETCoreApp,Version=v6.0). Package OpenTracing 0.12.1 does not support any target
 frameworks. [D:\UnrealEngine\Engine\Source\Programs\UnrealBuildTool\UnrealBuildTool.csproj]
D:\UnrealEngine\Engine\Source\Programs\Shared\EpicGames.Box\EpicGames.Box.csproj : error NU1202: Package Microsoft.Win3
2.Registry 5.0.0 is not compatible with net6.0 (.NETCoreApp,Version=v6.0). Package Microsoft.Win32.Registry 5.0.0 does
not support any target frameworks. [D:\UnrealEngine\Engine\Source\Programs\UnrealBuildTool\UnrealBuildTool.csproj]
D:\UnrealEngine\Engine\Source\Programs\Shared\EpicGames.Box\EpicGames.Box.csproj : error NU1202: Package System.Securit
y.AccessControl 5.0.0 is not compatible with net6.0 (.NETCoreApp,Version=v6.0). Package System.Security.AccessControl 5
.0.0 supports: uap10.0.16299 (UAP,Version=v10.0.16299) [D:\UnrealEngine\Engine\Source\Programs\UnrealBuildTool\UnrealBu
ildTool.csproj] ....

In order to start from a clean slate, I reinstalled my windows OS and repeated above steps to no avail. This is currently what shows as installed on my system:

dotnet --list-sdks
8.0.204 [C:\Program Files\dotnet\sdk]

dotnet --list-runtimes
Microsoft.AspNetCore.App 8.0.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 8.0.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 8.0.4 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

What is going on and how do I fix this? Any help would be appreciated

Edit:

I also receive this warning concerning packages being restored using .netframework versions other than ‘net6.0’:

D:\UnrealEngine\Engine\Source\Programs\Shared\EpicGames.Box\EpicGames.Box.csproj : warning NU1701: Package 'System.Data
.DataSetExtensions 4.5.0' was restored using '.NETFramework,Version=v4.6.1, .NETFramework,Version=v4.6.2, .NETFramework
,Version=v4.7, .NETFramework,Version=v4.7.1, .NETFramework,Version=v4.7.2, .NETFramework,Version=v4.8' instead of the p
roject target framework 'net6.0'. This package may not be fully compatible with your project. [D:\UnrealEngine\Engine\S
ource\Programs\UnrealBuildTool\UnrealBuildTool.csproj]

I noticed the cproj files (ex. UnrealEngine\Engine\Source\Programs\Shared\EpicGames.Box.csproj) within the unreal engine source list ‘net6.0’ in the targetframework field:

<PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>

is this incorrect?

2

Hi ! I 'm having a similar issue right now. I already had the engine built, I was working on my project, and I started getting errors about incompatibility with net6.0 out of the blue. (I seemingly didn’t touch anything related)

I tried to rebuild the engine, had to change the version of

<PackageReference Include=“Microsoft.Extensions.Logging.Console” Version=“5.0.0” / >
in
UnrealEngine\Engine\Source\Programs\UnrealBuildTool\UnrealBuildTool.csproj

to get past the same kind of error as the OP, but I get this when trying to build my project :

Failed to restore \UnrealEngine\Engine\Source\Programs\Shared\EpicGames.MongoDB\EpicGames.MongoDB.csproj (in 30 ms).
Failed to restore \UnrealEngine\Engine\Source\Programs\Shared\EpicGames.Redis\EpicGames.Redis.csproj (in 79 ms).
Failed to restore \UnrealEngine\Engine\Source\Programs\AutomationTool\SmartlingLocalization\SmartlingLocalization.Automation.csproj (in 230 ms).

// And many more...

1>------ Build started: Project: ****, Configuration: Development_Editor x64 ------
Failed to restore \UnrealEngine\Engine\Source\Programs\Shared\EpicGames.Perforce.Fixture\EpicGames.Perforce.Fixture.csproj (in 77 ms).
NuGet package restore failed. Please see Error List window for detailed warnings and errors.
1>Using bundled DotNet SDK version: 6.0.302

Using the dotnet restore command results in :

UnrealEngine\Engine\Source\Programs\Shared\EpicGames.MongoDB\EpicGames.MongoDB.csproj : error NU1202: Package AWSSDK.SecurityToken 3.7.100.14 is not compatible with net6.0 (.NETCoreApp,Version=v6.0). Package AWSSDK.SecurityToken 3.7.100.14 does not support any target frameworks. [E:\SpaceHex\HexD-Space\HexD_Space.sln]

with this same error for many different “systems”.

I spent hours looking for a solution but I don’t really understand what’s happening and couldn’t find anything :confused:

3

For an update for my situation I ended up re-downloading the unreal engine source but downloaded it to a different drive (my C:/ drive. Originally, I downloaded it to my D:/ drive). I repeated my steps above and generateprojectfiles.bat finally worked. It seems like unreal source expects to be downloaded to the C:/ drive? I’m not sure why yet but will continue to investigate and see if this can be changed. In my mind the engine should be able to be downloaded to any drive

4

Hi @Boagz I wasn’t sure when I saw your post but your report suggest that through your download files got corrupted, or perhaps a hard drive issue? I had the problem of damaged downloaded files from downloading through the DOS panel. Since, I download directly via GitHub without problems so far.

5

Hmm, maybe? I did just download to my laptop and was able to run GenerateProjectFiles.bat without much issue (a couple warnings but still completed). I would have to look a bit more into it to confirm