VSTS build: Packages failed to restore - Unable to resolve 'NETStandard.Library (>= 1.6.1)' for '.NETStandard,Version=v2.0'

Question

I'm getting

Unable to resolve 'NETStandard.Library (>= 1.6.1)' for '.NETStandard,Version=v2.0'.

in VSTS build using Hosted2017 build agent after I upgraded my aspnetcore app to netcoreapp2.0 and my libraries to use netstandard2.0.

Works fine locally.

I've edited my build definition to use .net core build task v2.* preview:

here is the build log:

Current agent version: '2.120.2'
Download all required tasks.
Downloading task: DotNetCoreCLI

Starting: Get Sources
Syncing repository: Liero/vyvojari-sk (GitHub)
...details ommited
HEAD is now at e448a25... Upgraded to .NET Core 2.0
Finishing: Get Sources

Starting: Restore
==============================================================================
Task         : .NET Core
Description  : Build, test, package, or publish a dotnet application, or run a custom dotnet command. For package commands, supports NuGet.org and authenticated feeds like Package Management and MyGet.
Version      : 2.0.5
Author       : Microsoft Corporation
Help         : [More Information](https://go.microsoft.com/fwlink/?linkid=832194)
==============================================================================
SYSTEMVSSCONNECTION exists true
Downloading: https://dist.nuget.org/win-x86-commandline/v4.0.0/nuget.exe
Caching tool: NuGet 4.0.0 x64
Using version: 4.0.0
Found tool in cache: NuGet 4.0.0 x64
Saving NuGet.config to a temporary config file.
Can\'t find loc string for key: NGCommon_NoSourcesFoundInConfig
NGCommon_NoSourcesFoundInConfig d:\a\1\Nuget\tempNuGet_734.config
"C:\Program Files\dotnet\dotnet.exe" restore d:\a\1\s\src\CommandStack\CommandStack.csproj --configfile d:\a\1\Nuget\tempNuGet_734.config --verbosity Detailed
  Restoring packages for d:\a\1\s\src\CommandStack\CommandStack.csproj...
C:\Program Files\dotnet\sdk\1.0.4\NuGet.targets(97,5): error : Unable to resolve 'NETStandard.Library (>= 1.6.1)' for '.NETStandard,Version=v2.0'. [d:\a\1\s\src\CommandStack\CommandStack.csproj]
  Generating MSBuild file d:\a\1\s\src\CommandStack\obj\CommandStack.csproj.nuget.g.props.
  Generating MSBuild file d:\a\1\s\src\CommandStack\obj\CommandStack.csproj.nuget.g.targets.
  Writing lock file to disk. Path: d:\a\1\s\src\CommandStack\obj\project.assets.json
  Restore failed in 115.64 ms for d:\a\1\s\src\CommandStack\CommandStack.csproj.

  Errors in d:\a\1\s\src\CommandStack\CommandStack.csproj
      Unable to resolve 'NETStandard.Library (>= 1.6.1)' for '.NETStandard,Version=v2.0'.

  NuGet Config files used:
      d:\a\1\Nuget\tempNuGet_734.config
Error: C:\Program Files\dotnet\dotnet.exe failed with return code: 1
Packages failed to restore
******************************************************************************
Finishing: Restore
******************************************************************************

and here is the source code: https://github.com/Liero/vyvojari-sk/tree/e448a25fb8c481704e9102aaaeb8b84b9aee7b02

Rosenquist

Looks like the 1.0.4 SDK is used on the agent and the hosted agent probably wasn't yet updated with the 2.0.0 SDK – Goldarn

But you see that v2.0.5 is used in the restore task – Rosenquist

that's the task. I see C:\Program Files\dotnet\sdk\1.0.4 – Goldarn

I've also added .NET Core Tool Installer task that install v2.0.0 and still the same output – Rosenquist

Hmm, it looks like when I checked "Feed(s) I select here" rather than preselected "Feeds in my NuGet.config" and make sure that "Use packages from NuGet.org" is also checked it works. Could someone verify this? – Rosenquist

Answer 1

Update 18/09/2017

Step 2 is no longer needed. I've left it in the solution though as it may still help some people. Thanks, @Liero for point this out.

---

Original Answer

I've just experienced this problem too and solved it by doing three things:

1. Use the .NET Core SDK(! - not runtime!) version 2.0.0:

2. Use the latest NuGet feed (4.3.0):

3. Restore your packages:

Update It's worth mentioning here that you should specify where you get your NuGet packages from. Most applications will probably just use the NuGet.org feed, as per the screenshot (see small checkbox), but you may have your custom feeds specified in a NuGet.config file. In that case, tick 'Feeds in my NuGet.config' and then specify the path to that file.

To illustrate the order, this is my working queue:

I hope this helps you and anyone else who has come up against this problem. If you have any questions, let me know. :)

Ramrod

In my case it worked also when I disabled use Use Nuget 4.3 (resp 4.* in my case), but maybe its because the tool was already cached. – Rosenquist

Amazing. My hat's off to you, friend! – Keli

I'm still getting error "Error: d:\a_tool\dncs\2.0.0\x64\dotnet.exe failed with return code: 1 Packages failed to restore" – Pastoralize

@PankajRawat are you sure you're using the latest version of nuget and have you told it to get your packages from nuget.org (if you don't have a packages directory)? – Ramrod

@ChrisPaton Yes I don't have package directory. s28.postimg.org/bj340omd9/Capture.jpg – Pastoralize

@PankajRawat what is the output from your restore log when it fails? – Ramrod

Thanks a lot. Worked like a charm. Microsoft better document this. – Concerned

@ChrisPaton. error I'm getting on restore "error NU1003: PackageTargetFallback and AssetTargetFallback cannot be used together. Remove PackageTargetFallback(deprecated) references from the project environment.", See detail error log 1drv.ms/u/s!At8hAhHRFiWTwA43mlwqiW1P7Gbt – Pastoralize

@PankajRawat I would suggest doing what the error says and remove PackageTargetFallback as it is deprecated! :) – Ramrod

@ChrisPaton. It's working. thank u so much. github.com/dotnet/buildtools/commit/… – Pastoralize

maybe this would work if I would know what IDE you are using and how to get to the screens you posted. Could you please update! – Bordello

@AndreiDobrin this question is about VSTS build configurations. The OP posted pictures from VSTS so I assumed a certain level of knowledge. Anyone familiar with VSTS will recognise these images. IDE is irrelevant here. – Ramrod

Great help, thanks! In my case I had to leave "Feeds in my NuGet.config" toggled as I am using the aspnet-contrib feed as well as the NuGet feed and otherwise it could not resolve aspnet-contrib packages. – Battat

Steps 1 and 2 worked for me, but step 3 did not. Instead I changed the Version of the NuGet from 1.* to 2.*. Possibly this is a timing issue as by now VSTS improved their support. Ludicrous how Microsoft's build servers don't support their stuff when they release it. But anyway, now I have to come back here later I guess and keep manually increasing the NuGet version? Annoying. I want a "Always use latest version" option. – Finnell

@ChrisPaton: it looks like step 2 (Nuget Installer Task) is no more required. – Rosenquist

These steps didn't work for me, sadly. I still experience this error. – Villager

@ChrisPaton: Maybe you should add to your step 3, that "Feed(s) I select here" option has to be checked OR you have to have nuget.config in your sources – Rosenquist

I've made that change, @Liero. – Ramrod

Sorry to hear that @Keli Collins. After adding these steps, where does your build process fail? – Ramrod

@ChrisPaton it turned out that I needed to be sure that the packet install command was run prior to any of the rest of it. Isaac Abraham has provided a very helpful extension package for VSTS (F# Helpers for VSTS) that includes a task to do just that. – Villager

Answer 2

You should select Feed(s) I select here for Feeds to use option. If you leave Use packages from this VSTS/TFS feed empty, packages will be downloaded from https://dist.nuget.org/.

Else, if you want to use Feeds in my NuGet.config as Feeds to use, you should specify the path for your NuGet.config file.

Cynical

Actually, it works with both .NET Core task 2.* (preview) and 1.*, but I had to add .NET Core Tool Installer build task. Could it be that my build agent was not updated yet? In 2.* of the restore task, I had to unselect "Feeds in my Nuget.config", since I have none. Maybe it could default to nuget.org package source? – Rosenquist

Thank you. However, this step alone is not sufficient. Without the .NET Core Tool Installer build task it does not work in my case. – Rosenquist

Ok, since you have solved the problem, you can add an answer for your steps and mark it. Or if your solved steps as Chris mentioned in the other answer, you can mark his answer. And it will also benefit others who have similar questions. – Cynical

Answer 3

I have received a similar error after generating a project using dotnet new angular which created a project relying on netcoreapp2.0. Inspection of project properties revealed that version 2.0 was not properly recognized (did not appear in the installed framework list).

Solution was to update Visual Studio 2017, as the minimum version required to support netcoreapp2.0 projects seems to be 15.3.1.

Gaidano

Answer 4

What worked for me was installing .NET Core SDK 2.0 and making the following changes:

in .csproj:

change

<TargetFramework>netcoreapp1.1.0</TargetFramework>

to

<TargetFramework>netcoreapp2.0</TargetFramework>

and in global.json:

"sdk": { "version": "1.1.0" }

to

"sdk": { "version": "2.0.0" }

I didn't know how to use Chris Paton' solution

Bordello

Answer 5

Updating the Visual Studio 2017 to latest 15.4.1 version resolved the problem for me.

Tease

Are you sure? Because this problem is related to VSTS not Visual Studio? – Rosenquist

I was getting same error with Visual Studio build after upgrading to .netCore 2.0. I had Visual studio version 15.2. Problem was resolved after updating visual studio to latest version 15.4.1 – Tease