Dim P As Range, t, x As String, i As Long
If TextBox1 = "" Or TextBox2 = "" Or ComboBox1 = "" Then Exit Sub
Set P = Intersect(Sheets("base2").[A:C], Sheets("base2").UsedRange.EntireRow)
t = P 'matrice, plus rapide
x = TextBox2 & Chr(1) & TextBox1 & Chr(1) & ComboBox1
For i = 1 To UBound(t)
If t(i, 1) & Chr(1) & t(i, 2) & Chr(1) & t(i, 3) = x Then
MsgBox "Cette formation existe déjà !", vbExclamation, "Service formation"
Exit Sub
End If
Next
'suite du code