Email: Subject Title

Does anyone know how to put in a file reference number automatically into the subject bar of an email?

This is the code that i am currently using:

On Error GoTo Err_Handler
MsgBox "THIS FEATURE WILL ONLY EXPORT FILES WITH TODAYS REFDATE"
If [CboExport] = "Today" Then
Dim rst As Recordset
Dim db As Database
Set db = CurrentDb
'Create Recordset
Set rst = db.OpenRecordset("SELECT tblAT.FileNr, tblAT.RefDate " & _
"FROM tblAT " & _
"WHERE (((tblAT.RefDate)=Date()));", dbOpenDynaset)
'Check to see if there has been records recorded today
If rst.EOF = True And rst.BOF = True Then
Beep
MsgBox "THERE ARE NO RECORDS WITH TODAYS DATE, REFER TO SPECIFIC DATE."
rst.Close
Set db = Nothing
Exit Sub
End If
'Export query as MS EXCELL

DoCmd.SendObject acSendQuery, "qryTodaysDate", acFormatXLS, company@somewhere.com, myboss@somewhere.com, , "File reference number ?????????"The following file is the latest extract from me as at " & Date & "."

regards, Steve