diff --git a/MSVCardour3/Ardour3.vcproj b/MSVCardour3/Ardour3.vcproj
index 77fcd01d73..0545f6252c 100644
--- a/MSVCardour3/Ardour3.vcproj
+++ b/MSVCardour3/Ardour3.vcproj
@@ -719,6 +719,10 @@
 				RelativePath="..\gtk2_ardour\interthread_progress_window.cc"
 				>
 			</File>
+			<File
+				RelativePath="..\gtk2_ardour\io_button.cc"
+				>
+			</File>
 			<File
 				RelativePath="..\gtk2_ardour\io_selector.cc"
 				>
@@ -1817,6 +1821,10 @@
 				RelativePath="..\gtk2_ardour\interthread_progress_window.h"
 				>
 			</File>
+			<File
+				RelativePath="..\gtk2_ardour\io_button.h"
+				>
+			</File>
 			<File
 				RelativePath="..\gtk2_ardour\io_selector.h"
 				>