Visual Studio 2017 cannot update Microsoft.NETCore.App package (“Blocked by project”)

.net corevisual-studio-2017

I have a dotnet core app that is targetting Microsoft.NETCore.App 1.1.2. I created a test project to test against that project but when building I noticed this warning:
enter image description here

I open the NuGet Package Manager and see that warning is correct, the project being tested has a different version of Microsoft.NETCore.App:
enter image description here
enter image description here

My problem is that Visual Studio is not letting me update that version, so I'm confused on how to solve this issue:
enter image description here
Ideally I would just click the dropdown and select the right version but Visual Studio claims that it cannot do this because of "additional constraints in the project or packages.config". How am I supposed to update that package? What "additional constraints" is Visual Studio referring to?

Best Answer

EDIT 2018: Only follow the instructions for updating the package if you really know what you are doing. In most cases, you never need to update this package - or other packages marked as "blocked by project" - manually. A framework-dependent app will use the latest runtime available and a self-contained application will perform an extra build using a newer version of this package automatically. (there are some edge cases where you need to upgrade this package in test projects. in this case, add <TargetLatestRuntimePatch>true</…> and see this Q&A for other options)

The implicit package references that the Microsoft.NET.Sdk infers can't be updated via NuGet.

If you migrated from project.json, the project with the 1.1.0 reference likely contains

<RuntimeFrameworkVersion>1.1.0</RuntimeFrameworkVersion>

in the csproj file or an item like this (if you may used the package manager previously to set the version):

<PackageReference Update="Microsoft.NETCore.App" Version="1.1.0" />

Delete entries like the above and all packages will reference 1.1.2 (or whatever the installed SDK considers to be the latest) automatically. Alernatively, set RuntimeFrameworkVersion in all projects.