diff --git a/rtl/objpas/rtlconst.inc b/rtl/objpas/rtlconst.inc
index 1763076341..3b7b363e25 100644
--- a/rtl/objpas/rtlconst.inc
+++ b/rtl/objpas/rtlconst.inc
@@ -259,6 +259,7 @@ ResourceString
   SSocketRead                   = 'Read';
   SSocketWrite                  = 'Write';
   SSortedListError              = 'Operation not allowed on sorted list';
+  SStreamInvalidSeek            = 'Invalid stream operation %s.Seek';   
   SStreamNoReading              = 'Reading from %s is not supported';
   SStreamNoWriting              = 'Writing to %s is not supported';
   SStreamSetSize                = 'Error setting stream size';