diff --git a/reactos/subsys/system/notepad/dialog.h b/reactos/subsys/system/notepad/dialog.h
index 98f4d1562c5..850be242409 100644
--- a/reactos/subsys/system/notepad/dialog.h
+++ b/reactos/subsys/system/notepad/dialog.h
@@ -51,7 +51,7 @@ VOID DIALOG_HelpAboutWine(VOID);
 VOID DIALOG_TimeDate(VOID);
 
 /* utility functions */
-VOID ShowLastError();
+VOID ShowLastError(void);
 BOOL FileExists(LPCWSTR szFilename);
 BOOL DoCloseFile(void);
 void DoOpenFile(LPCWSTR szFileName);