Pas de problème, dans le code ci-dessus, tu remplaces la ligne
Reference = MyWs.Range("C1").Value
par
Reference = "C1"
et ça devrait jouer parfaitement
voici la nouvelle procédure :
Option Explicit
Sub Insertion_Ligne()
Dim MyWs As Worksheet
Dim MyRange As Range, Cel As Range
Dim Reference As Variant
Dim FirstAd As String
Set MyWs = ThisWorkbook.ActiveSheet
Set MyRange = MyWs.Range("B1", Range("B1").End(xlDown))
Reference = "C1"
With MyRange
Application.ScreenUpdating = False
Set Cel = .Find(Reference, LookIn:=xlValues)
If Not Cel Is Nothing Then
FirstAd = Cel.Offset(1, 0).Address
Do
Cel.EntireRow.Insert
Set Cel = .FindNext(Cel)
Loop While Not Cel Is Nothing And Cel.Address <> FirstAd
End If
End With
Application.ScreenUpdating = True
End Sub