diff --git a/include/winreg.h b/include/winreg.h
index 2e0edb3caf7..25d77dc8a98 100644
--- a/include/winreg.h
+++ b/include/winreg.h
@@ -100,6 +100,7 @@ DWORD       WINAPI RegOpenCurrentUser(REGSAM,PHKEY);
 DWORD       WINAPI RegOpenKeyExW(HKEY,LPCWSTR,DWORD,REGSAM,PHKEY);
 DWORD       WINAPI RegOpenKeyExA(HKEY,LPCSTR,DWORD,REGSAM,PHKEY);
 #define     RegOpenKeyEx WINELIB_NAME_AW(RegOpenKeyEx)
+LONG        WINAPI RegOpenUserClassesRoot(HANDLE,DWORD,REGSAM,PHKEY);
 DWORD       WINAPI RegQueryInfoKeyW(HKEY,LPWSTR,LPDWORD,LPDWORD,LPDWORD,
                                       LPDWORD,LPDWORD,LPDWORD,LPDWORD,LPDWORD,
                                       LPDWORD,LPFILETIME);