diff --git a/components/lazutils/masks.pas b/components/lazutils/masks.pas
index 8cfb1f65fa..61d5c5e6b0 100644
--- a/components/lazutils/masks.pas
+++ b/components/lazutils/masks.pas
@@ -589,6 +589,7 @@ begin
   if fMaskEscapeChar>#127 then
     Exception_InvalidEscapeChar();
   fMaskEscapeChar:=AValue;
+  fMaskIsCompiled:=False;
 end;
 
 procedure TMaskBase.SetMaskOpCodesAllowed(AValue: TMaskOpCodes);