Export rows to another workbook but check for duplicates

Hi There,

I'm currently trying to send a range of data from a worksheet to another worksheet in a different workbook. However the code I'm using is only sending the top row, is it possible to send all rows?

I'm also trying to avoid sending duplicates. So if there is a matching row in the workbook it's being sent to the information won't be sent again.

The code I'm using is:

Sub Copy_To_Another_Workbook()
    Dim SourceRange As Range
    Dim DestRange As Range
    Dim DestWB As Workbook
    Dim DestSh As Worksheet
    Dim Lr As Long

    With Application
        .ScreenUpdating = False
        .EnableEvents = False
    End With


    If bIsBookOpen_RB("mastersheet.xls") Then
        Set DestWB = Workbooks("mastersheet.xls")
    Else
        Set DestWB = Workbooks.Open("C:\Users\Name\Desktop\New folder\mastersheet.xlsm")
    End If

    Set SourceRange = ThisWorkbook.Sheets("withdrawnsheet").Range("A2:T2")

    Set DestSh = DestWB.Worksheets("masterwithdrawn")


    Lr = LastRow(DestSh)
    Set DestRange = DestSh.Range("A" & Lr + 1)

    With SourceRange
        Set DestRange = DestRange.Resize(.Rows.Count, .Columns.Count)
    End With
    DestRange.Value = SourceRange.Value

    DestWB.Close savechanges:=True

    With Application
        .ScreenUpdating = True
        .EnableEvents = True
    End With
End Sub