Dlookup

Hi
in a ms db there are fields customer Name, address,Mobileno i want when user enter the mobile no other information should fill up automatically.for this first need a code to check the customer already exist or not.if not then a msg box appear that the customer is new please enter informstion manualy.
To do this what code should be Used???.

you use Form for you table so you can add Validation to MobileNo textbox.
on the Form design, click on MobileNo and add Code to it's BeforeUpdate event:

Code:

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private sub MobileNo_BeforeUpdate(Cancel As Integer)
Cancel = (DCount("1", "yourTableName", "MobileNo = '" & Me!MobileNo & "'")<>0)
If Cancel Then
  Msgbox "Mobile number belongs to another person!"
End If
end sub

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