Sub Blancs()
Dim X As Integer
Dim r As Range
X = CLng(InputBox(Prompt:="Quelle colonne?"))
If (X < 1) + (X > Columns.Count) Then Exit Sub
lastRow = ActiveSheet.Cells(Rows.Count, X).End(xlUp).Row
For Each r In Range(Cells(1, X), Cells(Rows.Count, X).End(xlUp))
If r.Value = "" Then
r.ClearContents
End If
Next
End Sub