Mac, Unreal Engine Version 5.4.3, Xcode 15.4
Error at a project creation time.
any idea?
Setting up bundled DotNet SDK
/Volumes/X5_2/Epic/UE_5.4/Engine/Build/BatchFiles/Mac/../../../Binaries/ThirdParty/DotNet/6.0.302/mac-x64
Running dotnet Engine/Binaries/DotNET/UnrealBuildTool/UnrealBuildTool.dll -projectfiles -project=/Volumes/X5_2/Epic/Projects/Start/Start.uproject -game -rocket -progress
Log file: /Users/jinbom/Library/Application Support/Epic/UnrealBuildTool/Log_GPF.txt
Generating XCode project files:
Discovering modules, targets and source code for project...
Total execution time: 20.71 seconds
UnrealBuildTool(0): error:System.Text.Json.JsonException: '0x00' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0. (in /Volumes/X5_2/Epic/UE_5.4/Engine/Plugins/2D/Paper2D/._Paper2D.uplugin)
---> System.Text.Json.JsonReaderException: '0x00' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0.
at System.Text.Json.ThrowHelper.ThrowJsonReaderException(Utf8JsonReader& json, ExceptionResource resource, Byte nextByte, ReadOnlySpan`1 bytes)
at System.Text.Json.Utf8JsonReader.ConsumeValue(Byte marker)
at System.Text.Json.Utf8JsonReader.ReadFirstToken(Byte first)
at System.Text.Json.Utf8JsonReader.ReadSingleSegment()
at System.Text.Json.Utf8JsonReader.Read()
at System.Text.Json.JsonDocument.Parse(ReadOnlySpan`1 utf8JsonSpan, JsonReaderOptions readerOptions, MetadataDb& database, StackRowStack& stack)
at System.Text.Json.JsonDocument.Parse(ReadOnlyMemory`1 utf8Json, JsonReaderOptions readerOptions, Byte[] extraRentedArrayPoolBytes, PooledByteBufferWriter extraPooledByteBufferWriter)
at System.Text.Json.JsonDocument.Parse(ReadOnlyMemory`1 json, JsonDocumentOptions options)
at System.Text.Json.JsonDocument.Parse(String json, JsonDocumentOptions options)
at EpicGames.Core.JsonObject.Parse(String text) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/Shared/EpicGames.Core/JsonObject.cs:line 289
at EpicGames.Core.JsonObject.Read(FileReference file) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/Shared/EpicGames.Core/JsonObject.cs:line 250
at UnrealBuildTool.PluginDescriptor.FromFile(FileReference FileName) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/PluginDescriptor.cs:line 380
--- End of inner exception stack trace ---
at UnrealBuildTool.PluginDescriptor.FromFile(FileReference FileName) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/PluginDescriptor.cs:line 388
at UnrealBuildTool.PluginInfo..ctor(FileReference InFile, PluginType InType) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/Plugins.cs:line 107
at UnrealBuildTool.Plugins.ReadPluginsFromDirectory(DirectoryReference RootDirectory, String Subdirectory, PluginType Type) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/Plugins.cs:line 591
at UnrealBuildTool.RulesCompiler.CreateEngineRulesAssembly(Boolean bUsePrecompiled, Boolean bSkipCompile, Boolean bForceCompile, ILogger Logger) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/RulesCompiler.cs:line 94
at UnrealBuildTool.RulesCompiler.<>c__DisplayClass9_0.<CreateProjectRulesAssembly>b__0(FileReference _) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/RulesCompiler.cs:line 254
at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
at UnrealBuildTool.RulesCompiler.CreateProjectRulesAssembly(FileReference ProjectFileName, Boolean bUsePrecompiled, Boolean bSkipCompile, Boolean bForceCompile, ILogger Logger) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/RulesCompiler.cs:line 247
at UnrealBuildTool.ProjectFileGenerator.AddProjectsForAllTargets(PlatformProjectGeneratorCollection PlatformProjectGenerators, List`1 AllGames, List`1 AllTargetFiles, String[] Arguments, List`1 EngineProjects, List`1 GameProjects, Dictionary`2 ProjectFileToUProjectFile, Dictionary`2 ProgramProjects, Dictionary`2 RulesAssemblies, ILogger Logger) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/ProjectFiles/ProjectFileGenerator.cs:line 2774
at UnrealBuildTool.ProjectFileGenerator.GenerateProjectFiles(PlatformProjectGeneratorCollection PlatformProjectGenerators, String[] Arguments, Boolean bCacheDataForEditor, ILogger Logger) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/ProjectFiles/ProjectFileGenerator.cs:line 1038
at UnrealBuildTool.GenerateProjectFilesMode.ExecuteAsync(CommandLineArguments Arguments, ILogger Logger) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/Modes/GenerateProjectFilesMode.cs:line 65
at UnrealBuildTool.UnrealBuildTool.Main(String[] ArgumentsArray) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/UnrealBuildTool.cs:line 660
Having the exact issue with UE 5.5.1 on M1 macOS 15.2 with XCode 16
Installed and creating an empty project on an external SSD ExFAT4
It was a fresh install but tried uninstalling and reinstalling anyway
Seeing that the above post has no replies, I am hopeless but also clueless
Setting up bundled DotNet SDK
/Volumes/_/_/epic/UE_5.5/Engine/Build/BatchFiles/Mac/../../../Binaries/ThirdParty/DotNet/8.0.300/mac-arm64
Running dotnet Engine/Binaries/DotNET/UnrealBuildTool/UnrealBuildTool.dll -projectfiles -project=/Volumes/_/_.uproject -game -rocket -progress
Log file: /Users/_/Documents/Library/Application Support/Epic/UnrealBuildTool/Log_GPF.txt
Generating XCode project files:
Discovering modules, targets and source code for project...
Total execution time: 23.61 seconds
._Paper2D.uplugin(0): error: JsonReaderException: '0x00' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0.
at System.Text.Json.ThrowHelper.ThrowJsonReaderException(Utf8JsonReader& json, ExceptionResource resource, Byte nextByte, ReadOnlySpan`1 bytes)
at System.Text.Json.Utf8JsonReader.ConsumeValue(Byte marker)
at System.Text.Json.Utf8JsonReader.ReadFirstToken(Byte first)
at System.Text.Json.Utf8JsonReader.ReadSingleSegment()
at System.Text.Json.Utf8JsonReader.Read()
at System.Text.Json.JsonDocument.Parse(ReadOnlySpan`1 utf8JsonSpan, JsonReaderOptions readerOptions, MetadataDb& database, StackRowStack& stack)
at System.Text.Json.JsonDocument.Parse(ReadOnlyMemory`1 utf8Json, JsonReaderOptions readerOptions, Byte[] extraRentedArrayPoolBytes, PooledByteBufferWriter extraPooledByteBufferWriter)
at System.Text.Json.JsonDocument.Parse(ReadOnlyMemory`1 json, JsonDocumentOptions options)
at System.Text.Json.JsonDocument.Parse(String json, JsonDocumentOptions options)
at EpicGames.Core.JsonObject.Parse(String text) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/Shared/EpicGames.Core/JsonObject.cs:line 289
at EpicGames.Core.JsonObject.Read(FileReference file) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/Shared/EpicGames.Core/JsonObject.cs:line 250
at UnrealBuildTool.PluginDescriptor.FromFile(FileReference FileName) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/PluginDescriptor.cs:line 395Wrapped by JsonException: '0x00' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0. (in /Volumes/KINGSTON/macosapps/epic/UE_5.5/Engine/Plugins/2D/Paper2D/._Paper2D.uplugin)
at UnrealBuildTool.PluginDescriptor.FromFile(FileReference FileName) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/PluginDescriptor.cs:line 403
at UnrealBuildTool.PluginInfo..ctor(FileReference InFile, PluginType InType) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/Plugins.cs:line 107
at UnrealBuildTool.Plugins.ReadPluginsFromDirectory(DirectoryReference RootDirectory, String Subdirectory, PluginType Type) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/Plugins.cs:line 591
at UnrealBuildTool.Plugins.ReadEnginePlugins(DirectoryReference EngineDirectory) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/Plugins.cs:line 351
at UnrealBuildTool.RulesCompiler.CreateEngineRulesAssembly(Boolean bUsePrecompiled, Boolean bSkipCompile, Boolean bForceCompile, ILogger Logger) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/System/RulesCompiler.cs:line 94
at UnrealBuildTool.ProjectFileGenerator.AddProjectsForAllTargets(PlatformProjectGeneratorCollection PlatformProjectGenerators, List`1 AllGames, List`1 AllTargetFiles, String[] Arguments, List`1 EngineProjects, List`1 GameProjects, Dictionary`2 ProjectFileToUProjectFile, Dictionary`2 ProgramProjects, Dictionary`2 RulesAssemblies, ILogger Logger) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/ProjectFiles/ProjectFileGenerator.cs:line 2777
at UnrealBuildTool.ProjectFileGenerator.GenerateProjectFiles(PlatformProjectGeneratorCollection PlatformProjectGenerators, String[] Arguments, Boolean bCacheDataForEditor, ILogger Logger) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/ProjectFiles/ProjectFileGenerator.cs:line 1048
at UnrealBuildTool.GenerateProjectFilesMode.ExecuteAsync(CommandLineArguments Arguments, ILogger Logger) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/Modes/GenerateProjectFilesMode.cs:line 260
at UnrealBuildTool.UnrealBuildTool.Main(String[] ArgumentsArray) in /Users/build/Build/++UE5/Sync/Engine/Saved/CsTools/Engine/Source/Programs/UnrealBuildTool/UnrealBuildTool.cs:line 687
Same issue with UE 5.5.1 when trying to generate Visual Studio project files on Windows. I created the project on a M3 Macbook Pro and transfered project files using a USB key.
In my case it occurs with AdvancedSessions plugin, it’s the only one in my project.
Generating VisualStudio project files:
Discovering modules, targets and source code for project...
Total execution time: 1.09 seconds
._AdvancedSessions.uplugin(0): error: JsonReaderException: '0x00' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0.
at System.Text.Json.ThrowHelper.ThrowJsonReaderException(Utf8JsonReader& json, ExceptionResource resource, Byte nextByte, ReadOnlySpan`1 bytes)
at System.Text.Json.Utf8JsonReader.ConsumeValue(Byte marker)
at System.Text.Json.Utf8JsonReader.ReadFirstToken(Byte first)
at System.Text.Json.Utf8JsonReader.ReadSingleSegment()
at System.Text.Json.Utf8JsonReader.Read()
at System.Text.Json.JsonDocument.Parse(ReadOnlySpan`1 utf8JsonSpan, JsonReaderOptions readerOptions, MetadataDb& database, StackRowStack& stack)
at System.Text.Json.JsonDocument.Parse(ReadOnlyMemory`1 utf8Json, JsonReaderOptions readerOptions, Byte[] extraRentedArrayPoolBytes, PooledByteBufferWriter extraPooledByteBufferWriter)
at System.Text.Json.JsonDocument.Parse(ReadOnlyMemory`1 json, JsonDocumentOptions options)
at System.Text.Json.JsonDocument.Parse(String json, JsonDocumentOptions options)
at EpicGames.Core.JsonObject.Parse(String text) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\Shared\EpicGames.Core\JsonObject.cs:line 289
at EpicGames.Core.JsonObject.Read(FileReference file) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\Shared\EpicGames.Core\JsonObject.cs:line 250
at UnrealBuildTool.PluginDescriptor.FromFile(FileReference FileName) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\System\PluginDescriptor.cs:line 395Wrapped by JsonException: '0x00' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0. (in C:\Users\gegva\Documents\1\Plugins\AdvancedSessions\._AdvancedSessions.uplugin)
at UnrealBuildTool.PluginDescriptor.FromFile(FileReference FileName) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\System\PluginDescriptor.cs:line 403
at UnrealBuildTool.PluginInfo..ctor(FileReference InFile, PluginType InType) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\System\Plugins.cs:line 107
at UnrealBuildTool.Plugins.ReadPluginsFromDirectory(DirectoryReference RootDirectory, String Subdirectory, PluginType Type) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\System\Plugins.cs:line 591
at UnrealBuildTool.Plugins.ReadProjectPlugins(DirectoryReference ProjectDirectory) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\System\Plugins.cs:line 362
at UnrealBuildTool.RulesCompiler.<>c__DisplayClass9_0.<CreateProjectRulesAssembly>b__0(FileReference _) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\System\RulesCompiler.cs:line 291
at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
at UnrealBuildTool.RulesCompiler.CreateProjectRulesAssembly(FileReference ProjectFileName, Boolean bUsePrecompiled, Boolean bSkipCompile, Boolean bForceCompile, ILogger Logger) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\System\RulesCompiler.cs:line 247
at UnrealBuildTool.ProjectFileGenerator.AddProjectsForAllTargets(PlatformProjectGeneratorCollection PlatformProjectGenerators, List`1 AllGames, List`1 AllTargetFiles, String[] Arguments, List`1 EngineProjects, List`1 GameProjects, Dictionary`2 ProjectFileToUProjectFile, Dictionary`2 ProgramProjects, Dictionary`2 RulesAssemblies, ILogger Logger) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\ProjectFiles\ProjectFileGenerator.cs:line 2791
at UnrealBuildTool.ProjectFileGenerator.GenerateProjectFiles(PlatformProjectGeneratorCollection PlatformProjectGenerators, String[] Arguments, Boolean bCacheDataForEditor, ILogger Logger) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\ProjectFiles\ProjectFileGenerator.cs:line 1048
at UnrealBuildTool.GenerateProjectFilesMode.ExecuteAsync(CommandLineArguments Arguments, ILogger Logger) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\Modes\GenerateProjectFilesMode.cs:line 260
at UnrealBuildTool.UnrealBuildTool.Main(String[] ArgumentsArray) in D:\build\++UE5\Sync\Engine\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\UnrealBuildTool.cs:line 687
Has anyone got updates for this? I’m trying to build a project on UE 5.5.2 and keep getting the same error as OP with the logs stating Paper2D is having issues.
I’ve even disabled Paper2D and it’s still giving me errors.