diff --git a/projects/VC90/SimGear.vcproj b/projects/VC90/SimGear.vcproj
index 7c2eed04..cb653c75 100644
--- a/projects/VC90/SimGear.vcproj
+++ b/projects/VC90/SimGear.vcproj
@@ -439,6 +439,22 @@
 		<Filter
 			Name="Lib_sgio"
 			>
+			<File
+				RelativePath="..\..\simgear\io\HTTPClient.cxx"
+				>
+			</File>
+			<File
+				RelativePath="..\..\simgear\io\HTTPClient.hxx"
+				>
+			</File>
+			<File
+				RelativePath="..\..\simgear\io\HTTPRequest.cxx"
+				>
+			</File>
+			<File
+				RelativePath="..\..\simgear\io\HTTPRequest.hxx"
+				>
+			</File>
 			<File
 				RelativePath="..\..\simgear\io\iochannel.cxx"
 				>
@@ -527,10 +543,6 @@
 				RelativePath="..\..\simgear\io\sg_socket_udp.hxx"
 				>
 			</File>
-			<File RelativePath="..\..\simgear\io\HTTPClient.cxx" ></File>
-			<File RelativePath="..\..\simgear\io\HTTPClient.hxx" ></File>
-			<File RelativePath="..\..\simgear\io\HTTPRequest.cxx" ></File>
-			<File RelativePath="..\..\simgear\io\HTTPRequest.hxx" ></File>
 		</Filter>
 		<Filter
 			Name="Lib_sgmagvar"
@@ -1011,10 +1023,6 @@
 				RelativePath="..\..\simgear\props\propertyObject.hxx"
 				>
 			</File>
-			<File
-				RelativePath="..\..\simgear\props\tiedpropertylist.hxx"
-				>
-			</File>
 			<File
 				RelativePath="..\..\simgear\props\props.cxx"
 				>
@@ -1031,6 +1039,10 @@
 				RelativePath="..\..\simgear\props\props_io.hxx"
 				>
 			</File>
+			<File
+				RelativePath="..\..\simgear\props\tiedpropertylist.hxx"
+				>
+			</File>
 		</Filter>
 		<Filter
 			Name="Lib_sgmodel"
@@ -1439,7 +1451,7 @@
 				RelativePath="..\..\simgear\scene\tgdb\userdata.hxx"
 				>
 			</File>
-		</Filter>
+		</Filter>
 		<Filter
 			Name="Lib_sgtsync"
 			>
@@ -1464,25 +1476,17 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\simgear\threads\SGThread.hxx"
+				RelativePath="..\..\simgear\threads\SGThread.cxx"
 				>
 			</File>
 			<File
-				RelativePath="..\..\simgear\threads\SGThread.cxx"
+				RelativePath="..\..\simgear\threads\SGThread.hxx"
 				>
 			</File>
 		</Filter>
 		<Filter
 			Name="Lib_sgstructure"
 			>
-			<File
-				RelativePath="..\..\simgear\structure\SGAtomic.hxx"
-				>
-			</File>
-			<File
-				RelativePath="..\..\simgear\structure\SGAtomic.cxx"
-				>
-			</File>
 			<File
 				RelativePath="..\..\simgear\structure\callback.hxx"
 				>
@@ -1547,6 +1551,14 @@
 				RelativePath="..\..\simgear\structure\OSGVersion.hxx"
 				>
 			</File>
+			<File
+				RelativePath="..\..\simgear\structure\SGAtomic.cxx"
+				>
+			</File>
+			<File
+				RelativePath="..\..\simgear\structure\SGAtomic.hxx"
+				>
+			</File>
 			<File
 				RelativePath="..\..\simgear\structure\SGBinding.cxx"
 				>
@@ -1563,6 +1575,14 @@
 				RelativePath="..\..\simgear\structure\SGExpression.hxx"
 				>
 			</File>
+			<File
+				RelativePath="..\..\simgear\structure\SGPerfMon.cxx"
+				>
+			</File>
+			<File
+				RelativePath="..\..\simgear\structure\SGPerfMon.hxx"
+				>
+			</File>
 			<File
 				RelativePath="..\..\simgear\structure\SGReferenced.hxx"
 				>