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Update ASP.NET Core web application to .NETCoreApp1.1 causes a project loading failure
If you are using Visual Studio 2017 RC to develop an ASP.NET Core web application, you may run into this stressful problem, which will unload your web application project after you update this project to target the .NETCoreApp1.1 framework. This loading problem will appear after you rebuild your project and close the Visual Studio 2017 RC instance (you may have some other little issues before closing your VS instance).
When you re-open your project with Visual Studio, your ASP.NET Core web application will not load and you will get this error message from Visual Studio:
In the log file, you will have something like this:
=====================
12/01/2017 13:16:45
Recoverable
System.AggregateException: One or several errors occured. ---> System.ArgumentNullException: The value cannot be null.
Name of parameter : key
Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.TreeService.EnsureNotFaultedTree(IProjectVersionedValue`1 appliedValue)
Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.TreeService.<PublishTreeAsync>d__66.MoveNext()
--- Fin de la trace de la pile d'exception interne ---
---> (Exception interne #0) System.ArgumentNullException: The value cannot be null.
Name of parameter : key
Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.TreeService.EnsureNotFaultedTree(IProjectVersionedValue`1 appliedValue)
Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Package.TreeService.<PublishTreeAsync>d__66.MoveNext()<---
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The solution is simple and takes just a few seconds to complete. Here are the steps to follow:
- 1 Close your instance of Visual Studio 2017 RC
- 2 Delete all bin and obj objects of your web application project
- 3 Re-open your solution in Visual Studio 2017 RC, your .NETCoreApp 1.1 project will be correctly loaded
- 4 Add the NuGet package Microsoft.DiaSymReader.Native, version 1.5.0-beta2-24728
January 12, 2016