diff --git a/esp8266/webinterface.cpp b/esp8266/webinterface.cpp
index 22d144c1..6a98d265 100644
--- a/esp8266/webinterface.cpp
+++ b/esp8266/webinterface.cpp
@@ -18,7 +18,7 @@
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
-#include <PgmSpace.h>
+#include <pgmspace.h>
 #include "config.h"
 #include "webinterface.h"
 #include "wifi.h"