diff --git a/PC/VC6/pythoncore.dsp b/PC/VC6/pythoncore.dsp
index 756e271cabc..38d450ba919 100644
--- a/PC/VC6/pythoncore.dsp
+++ b/PC/VC6/pythoncore.dsp
@@ -519,6 +519,10 @@ SOURCE=..\..\Modules\md5module.c
 # End Source File
 # Begin Source File
 
+SOURCE=..\..\Objects\memoryobject.c
+# End Source File
+# Begin Source File
+
 SOURCE=..\..\Parser\metagrammar.c
 # End Source File
 # Begin Source File
diff --git a/PC/VS7.1/pythoncore.vcproj b/PC/VS7.1/pythoncore.vcproj
index 601bfa096b2..672db124afb 100644
--- a/PC/VS7.1/pythoncore.vcproj
+++ b/PC/VS7.1/pythoncore.vcproj
@@ -658,6 +658,9 @@
 		<File
 			RelativePath="..\..\Modules\md5module.c">
 		</File>
+		<File
+			RelativePath="..\..\Objects\memoryobject.c">
+		</File>
 		<File
 			RelativePath="..\..\Parser\metagrammar.c">
 		</File>
diff --git a/PC/VS8.0/pythoncore.vcproj b/PC/VS8.0/pythoncore.vcproj
index d1be2683374..e0a53372a15 100644
--- a/PC/VS8.0/pythoncore.vcproj
+++ b/PC/VS8.0/pythoncore.vcproj
@@ -1458,6 +1458,10 @@
 				RelativePath="..\..\Objects\longobject.c"
 				>
 			</File>
+			<File
+				RelativePath="..\..\Objects\memoryobject.c"
+				>
+			</File>
 			<File
 				RelativePath="..\..\Objects\methodobject.c"
 				>
diff --git a/PCbuild/pythoncore.vcproj b/PCbuild/pythoncore.vcproj
index 0d3d71e405a..1b9056a5b45 100644
--- a/PCbuild/pythoncore.vcproj
+++ b/PCbuild/pythoncore.vcproj
@@ -1458,6 +1458,10 @@
 				RelativePath="..\Objects\longobject.c"
 				>
 			</File>
+			<File
+				RelativePath="..\Objects\memoryobject.c"
+				>
+			</File>
 			<File
 				RelativePath="..\Objects\methodobject.c"
 				>