Using Unity 2018.3.0f2.
Downloaded and launched the 2D Game Kit tutorial from UnityHub.
Popup comes up warning of an error that should not happen on first launch; asked me to report.
Running Mac OSX Mojave 10.14.2 on a MacBook Pro
Error details:
Assets/2DGamekit/Utilities/CinemachinePostProcessingV2/CinemachinePostProcessing.cs(28,6): error CS0012: The type ‘Attribute’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Assets/2DGamekit/Utilities/CinemachinePostProcessingV2/CinemachinePostProcessing.cs(31,6): error CS0616: ‘SaveDuringPlay’ is not an attribute class
Assets/2DGamekit/Utilities/CinemachinePostProcessingV2/CinemachinePostProcessing.cs(28,57): error CS0012: The type ‘Enum’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Assets/2DGamekit/Utilities/CinemachinePostProcessingV2/CinemachinePostProcessing.cs(84,46): error CS0012: The type ‘ValueType’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Assets/2DGamekit/Utilities/CinemachinePostProcessingV2/CinemachinePostProcessing.cs(82,33): error CS0012: The type ‘Enum’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Can you check your settings and see if you’re using .NET 4.x Equivalent for Scripting Runtime Version?
Edit > Project Settings > Player > Other Settings > Configuration > Scripting Runtime Version > .NET 4.x Equivalent
5 Likes
@ed_s Thank you! Had the same issue, and it now worked! 
Hello, Thank you for your reply, I did change the setting to “.NET 4.x Equivalent” as suggested by you but that still did not get rid of the errors for me. I am an absolute beginner and I have the following errors just right after launching the 2d Tutorial for the first time. I would be really grateful if you can help me solve my issue.
Thank you.
Error#1
Socket: bind failed, error: An attempt was made to access a socket in a way forbidden by its access permissions.
(0)
Error#2
Unable to join player connection multicast group.
Error#3
Assets\2DGamekit\Utilities\CinemachinePostProcessingV2\CinemachinePostProcessing.cs(28,6): error CS0012: The type ‘Attribute’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Error#4
Assets\2DGamekit\Utilities\CinemachinePostProcessingV2\CinemachinePostProcessing.cs(31,6): error CS0012: The type ‘Attribute’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Error#5
Assets\2DGamekit\Utilities\CinemachinePostProcessingV2\CinemachinePostProcessing.cs(28,57): error CS0012: The type ‘Enum’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Error#6
Assets\2DGamekit\Utilities\CinemachinePostProcessingV2\CinemachinePostProcessing.cs(28,63): error CS0012: The type ‘Enum’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Error#7
Assets\2DGamekit\Utilities\CinemachinePostProcessingV2\CinemachinePostProcessing.cs(28,6): error CS0012: The type ‘Enum’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Error#8
Assets\2DGamekit\Utilities\CinemachinePostProcessingV2\CinemachinePostProcessing.cs(84,29): error CS0012: The type ‘Enum’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Error#9
Assets\2DGamekit\Utilities\CinemachinePostProcessingV2\CinemachinePostProcessing.cs(84,46): error CS0012: The type ‘ValueType’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Error#10
Assets\2DGamekit\Utilities\CinemachinePostProcessingV2\CinemachinePostProcessing.cs(82,33): error CS0012: The type ‘Enum’ is defined in an assembly that is not referenced. You must add a reference to assembly ‘netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51’.
Error#11
Element ‘UnityEditor.PackageManager.UI.PackageSearchFilterTabs’ has no registered factory method.
UnityEditor.PackageManager.UI.PackageManagerWindow:ShowPackageManagerWindow()
Error#21
Library\PackageCache\com.unity.package-manager-ui@1.9.11\Editor\Sources\UI\Common\PopupField.cs(8,36): error CS0246: The type or namespace name ‘BaseTextElement’ could not be found (are you missing a using directive or an assembly reference?)
Error#22
Library\PackageCache\com.unity.package-manager-ui@1.9.11\Editor\Sources\UI\Common\PopupField.cs(118,33): error CS0115: ‘PopupField.ExecuteDefaultAction(EventBase)’: no suitable method found to override
Error#23
Library\PackageCache\com.unity.package-manager-ui@1.9.11\Editor\Sources\UI\Common\PopupField.cs(8,53): error CS0535: ‘PopupField’ does not implement interface member ‘INotifyValueChanged.SetValueWithoutNotify(T)’
Error#24
Library\PackageCache\com.unity.package-manager-ui@1.9.11\Editor\Sources\UI\Common\PopupField.cs(8,53): error CS0535: ‘PopupField’ does not implement interface member ‘INotifyValueChanged.RemoveOnValueChanged(EventCallback<ChangeEvent>)’
Error#12 to 20 are similar long ones
NullReferenceException: Object reference not set to an instance of an object
UnityEditor.PackageManager.UI.PackageList.ShowResults (UnityEditor.PackageManager.UI.PackageItem item) (at Library/PackageCache/com.unity.package-manager-ui@2.0.3/Editor/Sources/UI/PackageList.cs:62)
UnityEditor.PackageManager.UI.PackageFiltering.FilterPackageList (UnityEditor.PackageManager.UI.PackageList packageList) (at Library/PackageCache/com.unity.package-manager-ui@2.0.3/Editor/Sources/UI/PackageFiltering.cs:93)
UnityEditor.PackageManager.UI.PackageList.SetPackages (System.Collections.Generic.IEnumerable1[T] packages) (at Library/PackageCache/com.unity.package-manager-ui@2.0.3/Editor/Sources/UI/PackageList.cs:318) UnityEditor.PackageManager.UI.PackageCollection.UpdatePackageCollection (System.Boolean rebuildDictionary) (at Library/PackageCache/com.unity.package-manager-ui@2.0.3/Editor/Sources/Services/Packages/PackageCollection.cs:148) UnityEditor.PackageManager.UI.PackageList.Reload () (at Library/PackageCache/com.unity.package-manager-ui@2.0.3/Editor/Sources/UI/PackageList.cs:246) UnityEditor.PackageManager.UI.PackageList..ctor () (at Library/PackageCache/com.unity.package-manager-ui@2.0.3/Editor/Sources/UI/PackageList.cs:49) System.Reflection.MonoCMethod.InternalInvoke (System.Object obj, System.Object[ ] parameters) (at <ac823e2bb42b41bda67924a45a0173c3>:0) Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation. System.Reflection.MonoCMethod.InternalInvoke (System.Object obj, System.Object[ ] parameters) (at <ac823e2bb42b41bda67924a45a0173c3>:0) System.RuntimeType.CreateInstanceMono (System.Boolean nonPublic) (at <ac823e2bb42b41bda67924a45a0173c3>:0) System.RuntimeType.CreateInstanceSlow (System.Boolean publicOnly, System.Boolean skipCheckThis, System.Boolean fillCache, System.Threading.StackCrawlMark& stackMark) (at <ac823e2bb42b41bda67924a45a0173c3>:0) System.RuntimeType.CreateInstanceDefaultCtor (System.Boolean publicOnly, System.Boolean skipCheckThis, System.Boolean fillCache, System.Threading.StackCrawlMark& stackMark) (at <ac823e2bb42b41bda67924a45a0173c3>:0) System.Activator.CreateInstance (System.Type type, System.Boolean nonPublic) (at <ac823e2bb42b41bda67924a45a0173c3>:0) System.Activator.CreateInstance (System.Type type) (at <ac823e2bb42b41bda67924a45a0173c3>:0) UnityEngine.Experimental.UIElements.UxmlFactory2[TCreatedType,TTraits].Create (UnityEngine.Experimental.UIElements.IUxmlAttributes bag, UnityEngine.Experimental.UIElements.CreationContext cc) (at C:/buildslave/unity/build/Modules/UIElements/UXML/UxmlFactory.cs:244)
UnityEngine.Experimental.UIElements.VisualElementAsset.Create (UnityEngine.Experimental.UIElements.CreationContext ctx) (at C:/buildslave/unity/build/Modules/UIElements/UXML/VisualElementAsset.cs:113)
UnityEngine.Experimental.UIElements.VisualTreeAsset.CloneSetupRecursively (UnityEngine.Experimental.UIElements.VisualElementAsset root, System.Collections.Generic.Dictionary2[TKey,TValue] idToChildren, UnityEngine.Experimental.UIElements.CreationContext context) (at C:/buildslave/unity/build/Modules/UIElements/UXML/VisualTreeAsset.cs:161) UnityEngine.Experimental.UIElements.VisualTreeAsset.CloneSetupRecursively (UnityEngine.Experimental.UIElements.VisualElementAsset root, System.Collections.Generic.Dictionary2[TKey,TValue] idToChildren, UnityEngine.Experimental.UIElements.CreationContext context) (at C:/buildslave/unity/build/Modules/UIElements/UXML/VisualTreeAsset.cs:208)
UnityEngine.Experimental.UIElements.VisualTreeAsset.CloneSetupRecursively (UnityEngine.Experimental.UIElements.VisualElementAsset root, System.Collections.Generic.Dictionary2[TKey,TValue] idToChildren, UnityEngine.Experimental.UIElements.CreationContext context) (at C:/buildslave/unity/build/Modules/UIElements/UXML/VisualTreeAsset.cs:208) UnityEngine.Experimental.UIElements.VisualTreeAsset.CloneSetupRecursively (UnityEngine.Experimental.UIElements.VisualElementAsset root, System.Collections.Generic.Dictionary2[TKey,TValue] idToChildren, UnityEngine.Experimental.UIElements.CreationContext context) (at C:/buildslave/unity/build/Modules/UIElements/UXML/VisualTreeAsset.cs:208)
UnityEngine.Experimental.UIElements.VisualTreeAsset.CloneTree (UnityEngine.Experimental.UIElements.VisualElement target, System.Collections.Generic.Dictionary2[TKey,TValue] slotInsertionPoints) (at C:/buildslave/unity/build/Modules/UIElements/UXML/VisualTreeAsset.cs:150) UnityEngine.Experimental.UIElements.VisualTreeAsset.CloneTree (System.Collections.Generic.Dictionary2[TKey,TValue] slotInsertionPoints) (at C:/buildslave/unity/build/Modules/UIElements/UXML/VisualTreeAsset.cs:108)
UnityEditor.PackageManager.UI.PackageManagerWindow.OnEnable () (at Library/PackageCache/com.unity.package-manager-ui@2.0.3/Editor/Sources/UI/PackageManagerWindow.cs:33)
UnityEditor.PackageManager.UI.PackageManagerWindow:ShowPackageManagerWindow()
Thank you, this fixed me as well. (Mac OS High Sierra 10.13.6)
Thank you very much that fixed my problem!!