>However... it also blanks out the rest of the fields on my form and goes directy to the SAVE comand button... this I do NOT want ....

Thats because a REPLACE with the ALL clause moves the record pointer to EOF. Try this:

If this.value="Y"
	Select MyTable
	<b>lnRec = Recno()</b>
	Replace all complete with this.value for ;
	mytable.str_No=thisform.txtstr_no.value ;
	.AND. mytable.address=thisform.txtaddress.value 
	<b>go lnRec</b>
Endif