diff --git a/win_build/libboinc_2003.vcproj b/win_build/libboinc_2003.vcproj
index 8f943c2811..ec6b9c180a 100644
--- a/win_build/libboinc_2003.vcproj
+++ b/win_build/libboinc_2003.vcproj
@@ -337,6 +337,9 @@
 						CompileAs="2"/>
 				</FileConfiguration>
 			</File>
+			<File
+				RelativePath="..\lib\procinfo_win.C">
+			</File>
 			<File
 				RelativePath="..\lib\proxy_info.C">
 			</File>