Opening project in Visual Studio fails due to nuget.targets not found error

1. Install Nuget.
2. Right click on the solution and select "Enable NuGet Package Restore". In Visual Studio 2013 and later, select "Restore NuGet Packages" instead.
3. Click Ok on the warning.
4. Close and re-open the solution.

Should now be hunky-dory.

An alternative is to edit the .csproj file with a texteditor and remove or comment out the segment.