Pulling data from several workbooks to single Master workbook

I know there are about a thousand of these floating around on here but I cannot seem to find one that helps. Here is what I have so far

Sub Book1()
Application.ScreenUpdating = False
Dim Masterbook As Workbook
Dim Mybook As String
Dim Pathname As String
Dim i As Integer
Application.DisplayAlerts = False
Set Masterbook = ActiveWorkbook
    For i = 1 To 2
        Mybook = Range("M" & i).Text
        Pathname = "C:\Documents and Settings\leaxl49\Desktop"
        Workbooks.Open Filename:=Pathname & Mybook
        If i = 1 Then
            ActiveWorkbook.ActiveSheet.Range("B4:BB4").Copy Destination:=Masterbook.ActiveSheet.Range("B4:BB4")
            ActiveWorkbook.Close
        Else
            ActiveWorkbook.ActiveSheet.Range("B4:BB4").Copy Destination:=Masterbook.ActiveSheet.Range("F4:G")
            ActiveWorkbook.Close
    
        End If
    Next i
    Application.DisplayAlerts = True
End Sub

This is the error that I get when I try to run it

Run-time error '1004':
Application-defined or object defined error

I am trying to pull data from "Copy Recap" B4:B44 and put it in "Book 1" B4:B44 of the other workbook. I have no idea if the names are right in that code or not, it is just something that I found on here from February of last year.

thanks for the help