Visual Studio 15 CTP project refence error: An item with the caption "" already exists

Question

I try to use Visual Studio 2014 CTP 4 for developing, but for any project I open, I always get the same error on project loading:

An item with the caption "" already exists in the tree with the same sort order as the item being added.

References of project is empty with warning sign or without.

How do I resolve this issue?

K packages from myget.org/F/aspnetvnext

> C:\Users\user>kvm upgrade
Determining latest version
KRE-CLR-x86.1.0.0-beta2-10679 already installed.
Adding C:\Users\user\.kre\packages\KRE-CLR-x86.1.0.0-beta2-10679\bin to process PATH
Adding C:\Users\user\.kre\packages\KRE-CLR-x86.1.0.0-beta2-10679\bin to user PATH
Updating alias 'default' to 'KRE-CLR-x86.1.0.0-beta2-10679'

There is error info for https://github.com/aspnet/Logging/tree/2d54539a112e6d54c3d5de6dd825258c66787086

The project system has encountered an error.

An item with the caption "" already exists in the tree with the same sort order as the item being added.

_A diagnostic log has been written to the following location: "C:\Users\user\AppData\Local\Temp\VsProjectFault_28a9e6d4-ab42-441b-b4fe-124423dae4cb.failure.txt"._

and file content:

===================
09.11.2014 13:45:34
Recoverable
System.AggregateException: One or more errors occurred. ---> System.ArgumentException: An item with the caption "" already exists in the tree with the same sort order as the item being added.
 at Microsoft.VisualStudio.ProjectSystem.Designers.ProjectTree.Add(UnattachedProjectTreeNode node)
 at Microsoft.VisualStudio.ProjectSystem.Designers.ProjectTree.Add(IProjectTree subtree)
 at Microsoft.VisualStudio.Web.ProjectSystem.ReferencesSubTreeProvider.<>c__DisplayClass10.<BuildReferencesTreeAsync>b__12()
 at System.Threading.Tasks.Task`1.InnerInvoke()
 at System.Threading.Tasks.Task.Execute()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
 at Microsoft.VisualStudio.Web.ProjectSystem.ReferencesSubTreeProvider.<>c__DisplayClass8.<<ReferencesChanged>b__9>d__0.MoveNext()
 --- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task)
 at Microsoft.VisualStudio.ProjectSystem.Utilities.Designers.ProjectTreeProviderBase.<>c__DisplayClass0.<<Initialize>b__2>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
 at Microsoft.VisualStudio.ProjectSystem.Utilities.CommonProjectSystemTools.Rethrow(Exception ex)
 at Microsoft.VisualStudio.ProjectSystem.ProjectErrorReporting.<>c__DisplayClass4.<SubmitErrorReport>b__6()
 at Microsoft.VisualStudio.ProjectSystem.ExceptionFilter.<>c__DisplayClass0.<Guard>b__2()
 at GuardMethodClass.GuardMethod(Func`1 , Func`2 , Func`2 )
--- End of inner exception stack trace ---
---> (Inner Exception #0) System.ArgumentException: An item with the caption "" already exists in the tree with the same sort order as the item being added.
 at Microsoft.VisualStudio.ProjectSystem.Designers.ProjectTree.Add(UnattachedProjectTreeNode node)
 at Microsoft.VisualStudio.ProjectSystem.Designers.ProjectTree.Add(IProjectTree subtree)
 at Microsoft.VisualStudio.Web.ProjectSystem.ReferencesSubTreeProvider.<>c__DisplayClass10.<BuildReferencesTreeAsync>b__12()
 at System.Threading.Tasks.Task`1.InnerInvoke()
 at System.Threading.Tasks.Task.Execute()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
 at Microsoft.VisualStudio.Web.ProjectSystem.ReferencesSubTreeProvider.<>c__DisplayClass8.<<ReferencesChanged>b__9>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
 at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task)
 at Microsoft.VisualStudio.ProjectSystem.Utilities.Designers.ProjectTreeProviderBase.<>c__DisplayClass0.<<Initialize>b__2>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
 at Microsoft.VisualStudio.ProjectSystem.Utilities.CommonProjectSystemTools.Rethrow(Exception ex)
 at Microsoft.VisualStudio.ProjectSystem.ProjectErrorReporting.<>c__DisplayClass4.<SubmitErrorReport>b__6()
 at Microsoft.VisualStudio.ProjectSystem.ExceptionFilter.<>c__DisplayClass0.<Guard>b__2()
 at GuardMethodClass.GuardMethod(Func`1 , Func`2 , Func`2 )<---

Answer 1

Try checking all the new files you added in your project under which you are facing this error.

It might be the case that you renamed some of the files, however your csproj file is pointing to the older file. Then, it faces the conflict and throws this error.

Correcting the same should work.