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

21
votes

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:

build definition details

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

5
.net-coreazure-devopsazure-pipelines.net-core-2.0.net-standard-2.0
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 – Martin Ullrich
But you see that v2.0.5 is used in the restore task – Liero
that's the task. I see C:\Program Files\dotnet\sdk\1.0.4 – Martin Ullrich
I've also added .NET Core Tool Installer task that install v2.0.0 and still the same output – Liero
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? – Liero

5 Answers

63
votes

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: enter image description here

  2. Use the latest NuGet feed (4.3.0): enter image description here

  3. Restore your packages: enter image description here

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: enter image description here

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

4
votes

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/.

enter image description here

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.

1
votes

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.

0
votes

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

0
votes

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