VS2017 Juce 6 building Gain plugin error LNK1181

Why that error happen?

Severity Code Description Project File Line Suppression State
Error LNK1181 cannot open input file ‘GainPlugin.lib’ GainPlugin_VST3 D:\soft\juce-6.0.1-windows\JUCE\gainplugin\GainPlugin\Builds\VisualStudio2017\LINK 1

I’ve build it.