Can't build Unreal Engine. UnrealBuildTool.csproj: Error NU1100 : Unable to resolve

Problem

Can't build Unreal Engine project in Rider. Built output contains vast of errors like 0>UnrealBuildTool.csproj: Error NU1100 : Unable to resolve 'System.Management (>= 4.7.0)' for 'net6.0'. PackageSourceMapping is enabled, the following source(s) were not considered: Microsoft Visual Studio Offline Packages, nuget.org.

Cause

There is a problem with nuget.config file.

Resolution

Verify your Nuget.config. The path to the Nuget.config that is used by Rider can be found in the NuGet tool window. Click the node, so a new tab in the editor opens.

As a possible solution, replace its content with default:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <packageSources>
    <add key="nuget.org" value="https://api.nuget.org/v3/index.json" />
  </packageSources>
</configuration>