Unity 5.3.5 Universal 10- Cannot Build With IL2CPP

When trying to build a Universal 10 App I get the following error message when selecting IL2CPP backend, .NET seems to be ok. Finding it hard to debug it.

AssemblyResolutionException: Failed to resolve assembly: 'System.Runtime, Version=4.0.10.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
Mono.Cecil.BaseAssemblyResolver.Resolve (Mono.Cecil.AssemblyNameReference name, Mono.Cecil.ReaderParameters parameters)
Mono.Cecil.BaseAssemblyResolver.Resolve (Mono.Cecil.AssemblyNameReference name)
Mono.Cecil.DefaultAssemblyResolver.Resolve (Mono.Cecil.AssemblyNameReference name)
UnityEditor.MonoAssemblyStripping+<CollectAssembliesRecursive>c__AnonStorey6C.<>m__EA (Mono.Cecil.AssemblyNameReference a) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/MonoAssemblyStripping.cs:274)
System.Linq.Enumerable+<CreateSelectIterator>c__Iterator10`2[Mono.Cecil.AssemblyNameReference,Mono.Cecil.AssemblyDefinition].MoveNext ()
System.Linq.Enumerable+<CreateSelectManyIterator>c__Iterator12`2[Mono.Cecil.AssemblyDefinition,Mono.Cecil.AssemblyDefinition].MoveNext ()
System.Collections.Generic.HashSet`1[Mono.Cecil.AssemblyDefinition].UnionWith (IEnumerable`1 other)
UnityEditor.MonoAssemblyStripping.CollectAssembliesRecursive (IEnumerable`1 assemblies) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/MonoAssemblyStripping.cs:273)
UnityEditor.MonoAssemblyStripping.GenerateLinkXmlToPreserveDerivedTypes (System.String stagingArea, System.String librariesFolder, UnityEditor.RuntimeClassRegistry usedClasses) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/MonoAssemblyStripping.cs:241)
UnityEditorInternal.AssemblyStripper.RunAssemblyStripper (System.String stagingAreaData, IEnumerable assemblies, System.String managedAssemblyFolderPath, System.String[] assembliesToStrip, System.String[] searchDirs, System.String monoLinkerPath, IIl2CppPlatformProvider platformProvider, UnityEditor.RuntimeClassRegistry rcr, Boolean developmentBuild) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/AssemblyStripper.cs:182)
UnityEditorInternal.AssemblyStripper.StripAssemblies (System.String stagingAreaData, IIl2CppPlatformProvider platformProvider, UnityEditor.RuntimeClassRegistry rcr, Boolean developmentBuild) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/AssemblyStripper.cs:131)
UnityEditorInternal.IL2CPPBuilder.Run () (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/Il2Cpp/IL2CPPUtils.cs:201)
UnityEditorInternal.IL2CPPUtils.RunIl2Cpp (System.String tempFolder, System.String stagingAreaData, IIl2CppPlatformProvider platformProvider, System.Action`1 modifyOutputBeforeCompile, UnityEditor.RuntimeClassRegistry runtimeClassRegistry, Boolean developmentBuild) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/Il2Cpp/IL2CPPUtils.cs:128)
PostProcessUAPIl2Cpp.RunIL2CPP () (at C:/buildslave/unity/build/PlatformDependent/MetroPlayer/Extensions/Managed/PostProcessUAPIl2Cpp.cs:92)
PostProcessWinRT.Process () (at C:/buildslave/unity/build/PlatformDependent/WinRT/SharedSources/CSharp/PostProcessWinRT.cs:134)
UnityEditor.Metro.BuildPostprocessor.PostProcess (BuildPostProcessArgs args) (at C:/buildslave/unity/build/PlatformDependent/MetroPlayer/Extensions/Managed/ExtensionModule.cs:133)
UnityEditor.PostprocessBuildPlayer.Postprocess (BuildTarget target, System.String installPath, System.String companyName, System.String productName, Int32 width, Int32 height, System.String downloadWebplayerUrl, System.String manualDownloadWebplayerUrl, BuildOptions options, UnityEditor.RuntimeClassRegistry usedClassRegistry) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/PostprocessBuildPlayer.cs:316)
UnityEditor.HostView:OnGUI()

Any ideas?

You’re probably trying to use a plugin on il2cpp platform which is compiled against .NET Core, this is not allowed. You can only use plugins compiled against .NET 3.5 or lower.

Plugins compiled against .NET Core can only be used with scripting backend .NET .

Thanks for the clarification Tomas, I get it now… FYI im using Prime31 plugins for Universal Store. Probably this is causing the issue. I hope they update in future @prime31

i have same problem with Unity Built in IAP can anyone fix it when i am removing package from unity everything is working correct