Sub test()

    Dim WbookCheck As Workbook

    On Error Resume Next
    Set WbookCheck = Workbooks("Weekly Report.xls")
    On Error GoTo 0

    If WbookCheck Is Nothing then 'not open....

        filepaths = "c:\clients\work\Weekly Report.xls"

        If Dir(filepaths) = "" Then
            MsgBox "Please save the latest file under the name" & _
              " 'US Sector Flow Weekly Report' and run the macro again"
            Exit Sub
        Else
            'file exists - open it
            Set WbookCheck = Workbooks.Open(filepaths)
        End If
    End If

    with WbookCheck
        .Activate
        .Sheets("This week").Copy _
                Before:=Workbooks("Consolidated.xls").Sheets(1)
    end with

End Sub