diff --git a/lib/url.h b/lib/url.h
index f48cfaa14c..be11c8d06b 100644
--- a/lib/url.h
+++ b/lib/url.h
@@ -15,6 +15,9 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with BOINC.  If not, see <http://www.gnu.org/licenses/>.
 
+#ifndef URL_H
+#define URL_H
+
 #define URL_PROTOCOL_UNKNOWN 0
 #define URL_PROTOCOL_HTTP    1
 #define URL_PROTOCOL_HTTPS   2
@@ -39,3 +42,5 @@ extern void escape_project_url(char *in, char* out);
 extern bool valid_master_url(char*);
 extern void canonicalize_master_url(char *url);
 extern void canonicalize_master_url(std::string&);
+
+#endif
diff --git a/win_build/boinc_os_ss.vcproj b/win_build/boinc_os_ss.vcproj
index c0b1d6c651..c1303b71e7 100644
--- a/win_build/boinc_os_ss.vcproj
+++ b/win_build/boinc_os_ss.vcproj
@@ -650,6 +650,10 @@
 				RelativePath="..\lib\str_util.cpp"
 				>
 			</File>
+			<File
+				RelativePath="..\lib\url.cpp"
+				>
+			</File>
 			<File
 				RelativePath="..\lib\util.cpp"
 				>
@@ -747,6 +751,10 @@
 				RelativePath=".\stdafx.h"
 				>
 			</File>
+			<File
+				RelativePath="..\lib\url.h"
+				>
+			</File>
 			<File
 				RelativePath="..\lib\util.h"
 				>