Add rows based on the value of a cell.

It is probably because in line D instead of having a number there is text or something else
I can't say without seeing your file
Post an example of your file on cjoint.com, create a link that you copy and come back to paste it here

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"Imagination is more important than knowledge." A. Einstein

Good evening,

Here is a code that will duplicate your rows the desired number of times (entered in column D)
but by checking beforehand how many times the row is already present (by analyzing columns A to C). That is to say, if your row has already been duplicated during a first execution of the macro, it will not duplicate it again, or if needed, just the missing quantity.

Option Explicit Sub maj() Dim i, j, k, n, der As Long Dim cpte, dif, nbr As Integer Dim marque, nom, taille, px As String der = Range("A65536").End(xlUp).Row For n = 2 To der For i = 2 To der If Range("D" & i) > 1 Then cpte = 0 nbr = Range("D" & i).Value marque = Range("A" & i).Value nom = Range("B" & i).Value taille = Range("C" & i).Value Do While Range("A" & i).Offset(cpte, 0) = marque And Range("B" & i).Offset(cpte, 0) = nom And Range("C" & i).Offset(cpte, 0) = taille Range("D" & i).Offset(cpte, 0) = Range("D" & i).Value cpte = cpte + 1 Loop i = i + cpte - 1 If cpte < nbr Then dif = nbr - cpte Do While dif > 0 Rows(i + 1).Insert Shift:=xlDown, CopyOrigin:=xlFormatFromRightOrBelow Rows(i).Copy Rows(i + 1) Application.CutCopyMode = False i = i + 1 dif = dif - 1 der = der + 1 Loop End If End If Next i Next n End Sub

Have a good evening

Jc

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Let's save time: An example will always be more telling than a long prose, so post an example of your file and the expected result: