What happens if you remove the movefirst? Usually when you first open a recordset you are already starting with the first record.

You need to loop through header and detail too in order to by pass the error 40.  Here is my quick test:

o = new("SO_Invoice_bus", %sys_ss)

retval = o'movefirst()

while not(o'eof)

   retval = o'lines'movefirst()

   while not(o'lines'eof)

       retval = o'lines'getvalue("Valuation$", valuation$)

       if valuation$ = "5" or valuation$ = "6" {

           retval = o'lines'distribution'movefirst()

           while not(o'lines'distribution'eof)

               retval = o'lines'distribution'getvalue("LotSerialNo$", lotserial$); msgbox lotserial$

               retval = o'lines'distribution'movenext()

           wend

      }

       retval = o'lines'movenext()

   wend

   retval = o'movenext()

wend

drop object o

end

when the movefirst is removed the GetValue does not grab any  data and the same error is received when the MoveNext line is reached.

Thanks for your response.

If i set this up,  how do i call the distribution table?

The first two work and I can loop through the header and detail files, but the line below does not

retval = oTier.MoveFirst() returns a 0

do while oTier.EOF <> 1

 never enters the loop

Loop

Set oHead = oSession.AsObject(oSession.GetObject("SO_SalesOrder_bus"))

Set oLines = oHead.AsObject(oHead.Lines)

Set oTier = oLines.AsObject(oLines.Distribution)

thanks in advanced