[Bug] NU1101 cannot install Docfx

[HeKr09]

Describe the bug
I want to install docfx but I guess I am to stupid to do so.

To Reproduce
Run:
dotnet tool install -g docfx

C:\Users\me.me\AppData\Local\Temp\2aa18af5-d820-43c7-9428-1ca7f3cadd0e\restore.csproj : error NU1101: Unable
 to find package docfx. No packages exist with this id in source(s): Microsoft Visual Studio Offline Packages
The tool package could not be restored.
Tool 'docfx' failed to install. This failure may have been caused by:

* You are attempting to install a preview release and did not use the --version option to specify the version.
* A package by this name was found, but it was not a .NET tool.
* The required NuGet feed cannot be accessed, perhaps because of an Internet connection problem.
* You mistyped the name of the tool.

For more reasons, including package naming enforcement, visit https://aka.ms/failure-installing-tool

Expected behavior
An installation.

Context (please complete the following information):

• OS: Windows 10.0.19045 Build 19045
• Docfx version: None

Additional context
I have never installed docfx and I am working without any project right now.

[Lulalaby]

CNR on:

Edition	Windows 11 Enterprise Insider Preview
Version	        22H2
Installed on	‎31/‎07/‎2023
OS build	23511.1000
Experience	Windows Feature Experience Pack 1000.23511.1000.0

(oops, overseen that they only have offline packages)

[filzrev]

No packages exist with this id in source(s): Microsoft Visual Studio Offline Packages

It seems nuget.org feed is not included as package source.
What would be the result when running the following command?

dotnet nuget list source

On my windows environment. following message is displayed.

Registered Sources:
  1.  nuget.org [Enabled]
      https://api.nuget.org/v3/index.json
  2.  Microsoft Visual Studio Offline Packages [Enabled]
      C:\Program Files (x86)\Microsoft SDKs\NuGetPackages\

If nuget.org is not included in above command output. Then nuget packages souce is customized.
Try to find NuGet.config that affects package sources.

NuGet config file locations
https://learn.microsoft.com/en-us/nuget/consume-packages/configuring-nuget-behavior#config-file-locations-and-uses

[KalleOlaviNiemitalo]

@HeKr09 it looks like you are using only Visual Studio offline packages and not nuget.org. See sources command (NuGet CLI) for the command to check and configure that.

[HeKr09]

@filzrev @KalleOlaviNiemitalo
THat sounds good to me and my config is empty.

<?xml version="1.0"?>
<configuration>
  <packageSources>
  </packageSources>
</configuration>

dotnet nuget list source
Registered Sources:
  1.  Microsoft Visual Studio Offline Packages [Enabled]
      C:\Program Files (x86)\Microsoft SDKs\NuGetPackages\

According to the article I need to run:
nuget sources Enable -Name "nuget.org"
This does not work because PowerShell does not recognize the term nuget.

Can you tell me what to put in the config file?

[HeKr09]

@KalleOlaviNiemitalo @filzrev
Is there any chance to get an installation guide from you?

[filzrev]

For temporary workaround.
Try to explicitly specify additional NuGet package source when running install command.

dotnet tool install docfx -g --add-source https://api.nuget.org/v3/index.json

---

By default. NuGet package source is defined at %AppData%\Nuget\Nuget.Config.
With following settings.

  <packageSources>
    <add key="nuget.org" value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
    <add key="Microsoft Visual Studio Offline Packages" value="C:\Program Files (x86)\Microsoft SDKs\NuGetPackages\" />
  </packageSources>

On your environment. It seems nuget.org entry is removed for some reason.
For example.

• System administrator explicitly remove this entry to restrict nuget.org package access.
• Accidently remove nuget.org entry when using Visual Studio's setting pages.
• Manually placed NuGet.config file at Solution folder or any folder up to the drive root.
  and redefine package source with <clear/> tag.

[HeKr09]

Thank you very much!!!! This solved so many problems! :) It worked!