diff --git a/GreenshotPlugin/GreenshotPlugin.csproj b/GreenshotPlugin/GreenshotPlugin.csproj
index 9f31d9a67..5b8e82419 100644
--- a/GreenshotPlugin/GreenshotPlugin.csproj
+++ b/GreenshotPlugin/GreenshotPlugin.csproj
@@ -53,6 +53,7 @@
     <Compile Include="Interop\Base.cs" />
     <Compile Include="Interop\ComProgIdAttribute.cs" />
     <Compile Include="Interop\COMWrapper.cs" />
+    <Compile Include="Interop\IAppVisibility.cs" />
     <Compile Include="Interop\IDispatch.cs" />
     <Compile Include="Interop\IOleWindow.cs" />
     <Compile Include="Interop\IOleCommandTarget.cs" />