diff --git a/win/VC90/game.vcproj b/win/VC90/game.vcproj
index 8151b0b09a5..fceb9eda579 100644
--- a/win/VC90/game.vcproj
+++ b/win/VC90/game.vcproj
@@ -2936,6 +2936,14 @@
 						RelativePath="..\..\src\scripts\kalimdor\onyxias_lair\boss_onyxia.cpp"
 						>
 					</File>
+                                        <File
+                                                RelativePath="..\..\src\scripts\kalimdor\onyxias_lair\instance_onyxias_lair.cpp"
+                                                >
+                                        </File>
+                                        <File
+                                                RelativePath="..\..\src\scripts\kalimdor\onyxias_lair\onyxias_lair.h"
+                                                >
+                                        </File>
 				</Filter>
 				<Filter
 					Name="Razorfen Downs"