diff --git a/src/win/winapi.h b/src/win/winapi.h
index 0c125beb..f4f9145b 100644
--- a/src/win/winapi.h
+++ b/src/win/winapi.h
@@ -4610,6 +4610,30 @@ typedef NTSTATUS (NTAPI *sNtQueryDirectoryFile)
 # define ERROR_SYMLINK_NOT_SUPPORTED 1464
 #endif
 
+#ifndef ERROR_MUI_FILE_NOT_FOUND
+# define ERROR_MUI_FILE_NOT_FOUND 15100
+#endif
+
+#ifndef ERROR_MUI_INVALID_FILE
+# define ERROR_MUI_INVALID_FILE 15101
+#endif
+
+#ifndef ERROR_MUI_INVALID_RC_CONFIG
+# define ERROR_MUI_INVALID_RC_CONFIG 15102
+#endif
+
+#ifndef ERROR_MUI_INVALID_LOCALE_NAME
+# define ERROR_MUI_INVALID_LOCALE_NAME 15103
+#endif
+
+#ifndef ERROR_MUI_INVALID_ULTIMATEFALLBACK_NAME
+# define ERROR_MUI_INVALID_ULTIMATEFALLBACK_NAME 15104
+#endif
+
+#ifndef ERROR_MUI_FILE_NOT_LOADED
+# define ERROR_MUI_FILE_NOT_LOADED 15105
+#endif
+
 typedef BOOL (WINAPI *sGetQueuedCompletionStatusEx)
              (HANDLE CompletionPort,
               LPOVERLAPPED_ENTRY lpCompletionPortEntries,