Option Explicit
Sub RechercheSuivi()
Dim TNum(), TQté(), TRés(17001 To 18999, 1 To 2), L As Long, N As Long, Suivi As Worksheet, RngLig As Range
Set Suivi = Workbooks("2017_SUIVI LOTS - PROD & SC_factice.xlsm").Worksheets("EXPE CLIENTS BAGS-MECA")
Set RngLig = Suivi.Rows(3).Resize(Suivi.Cells(Suivi.Rows.Count, "D").End(xlUp).Row - 2)
TNum = RngLig.Columns("D").Value
TQté = RngLig.Columns("M").Value
For N = LBound(TRés, 1) To UBound(TRés, 1): TRés(N, 1) = N: Next N
On Error Resume Next
For L = 1 To UBound(TNum, 1)
N = TNum(L, 1)
TRés(N, 2) = TRés(N, 2) + TQté(L, 1)
Next L
Feuil1.[A1:B1999].Value = TRés
End Sub