diff --git a/Contrib/Modern UI/System.nsh b/Contrib/Modern UI/System.nsh
index a970ac27..c2219be3 100644
--- a/Contrib/Modern UI/System.nsh	
+++ b/Contrib/Modern UI/System.nsh	
@@ -146,14 +146,12 @@ Var MUI_TEMP2
 
 !macro MUI_HEADER_TEXT_PAGE TEXT SUBTEXT
 
-  !ifdef MUI_PAGE_HEADER_TEXT
-    !ifndef MUI_PAGE_HEADER_SUBTEXT
-      !insertmacro MUI_HEADER_TEXT "${MUI_PAGE_HEADER_TEXT}" "${SUBTEXT}"
-    !else
-      !insertmacro MUI_HEADER_TEXT "${MUI_PAGE_HEADER_TEXT}" "${MUI_PAGE_HEADER_SUBTEXT}"
-      !undef MUI_PAGE_HEADER_SUBTEXT
-    !endif
-    !undef MUI_PAGE_HEADER_TEXT
+  !ifdef MUI_PAGE_HEADER_TEXT & MUI_PAGE_HEADER_SUBTEXT
+    !insertmacro MUI_HEADER_TEXT "${MUI_PAGE_HEADER_TEXT}" "${MUI_PAGE_HEADER_SUBTEXT}"
+  !else ifdef MUI_PAGE_HEADER_TEXT
+    !insertmacro MUI_HEADER_TEXT "${MUI_PAGE_HEADER_TEXT}" "${SUBTEXT}"
+  !else ifdef MUI_PAGE_HEADER_SUBTEXT
+    !insertmacro MUI_HEADER_TEXT "${TEXT}" "${MUI_PAGE_HEADER_SUBTEXT}"
   !else
     !insertmacro MUI_HEADER_TEXT "${TEXT}" "${SUBTEXT}"
   !endif