Hi Cetin,
i didn't try IndexSeek() but i'll try for not using again again the tables. meanwhile i've added to first line this code and now there is no problem

if this.lcuniq and thisform.addmode=.t. or thisform.editmode=.t.
...

PS : when i add the "and _vfp.activeform.addmode=.t. or _vfp.activeform.aditmode=.t. " to the end of first line i was getting error i've changed to its thisform.addmode=.t. ...

TIA