Action avec "ENTER"

Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Column <> 9 Then Exit Sub 'si le changement a lieu ailleurs que dans la colonne I, sort de la procédure
'à l'édition colore l'interieur de la cellule en rouge ou supprime la couleur si cellule effacée
Target.Interior.ColorIndex = IIf(Target.Value <> "", 3, xlNone)
End Sub

Private Sub Worksheet_Change(ByVal Target As Range)
Set Target = Intersect(Target, Columns("I"))
If Target Is Nothing Then Exit Sub
Target.Interior.ColorIndex = IIf(Target.[COLOR="Red"]Cells(1, 1)[/COLOR] <> "", 3, xlNone)
End Sub

Private Sub Worksheet_Change(ByVal Target As Range)
Set Target = Intersect(Target, Columns("I"), Me.UsedRange)
If Target Is Nothing Then Exit Sub
For Each Target In Target
  Target.Interior.ColorIndex = IIf(Target <> "", 3, xlNone)
Next
End Sub

Private Sub Worksheet_Deactivate()
Application.OnKey "~"
End Sub

Private Sub Worksheet_Activate()
Application.OnKey , "entree"
End Sub

Private Sub Worksheet_Desactivate()
Application.OnKey , ""
End Sub

et dans un module :
Private Sub entree_Change(ByVal Target As Range)
Set Target = Intersect(Target, Columns("i"), Me.UsedRange)
If Target Is Nothing Then Exit Sub
For Each Target In Target
Target.Font.ColorIndex = IIf(Target <> "", 3, xlNone)
Next
End Sub

Private Sub Worksheet_Activate()
Application.OnKey "~", "Entree"
End Sub

Private Sub Worksheet_Deactivate()
Application.OnKey "~"
End Sub

'dans un module :

Sub Entree()
Dim Target As Range
Set Target = Intersect(Selection, Columns("I"), ActiveSheet.UsedRange)
If Target Is Nothing Then Exit Sub
For Each Target In Target
Target.Font.ColorIndex = IIf(Target <> "", 3, xlNone)
Next
End Sub