Hi RadzmarThanks for your replies.All working nowThanks!!!!

Hi AllI have encountered possible bugs in calculate.override.It seems that I cannot turn it off and allow the user to type freely, and then turn it on again.The situation simplifed:1) There are 3 text boxes, A, B and C.2) A and B are normal text boxes, free to type.3) C is set as 'Calculated - Read ...