Private Sub CommandButton7_Click()
Dim c As Range, r As Integer
Set c = Sheets("Feuil1").Columns("b").Find(ComboBox1)
r = c.row
Sheets("Feuil1").Rows(c.row).Delete shift:= xlup ' OK
Sheets("Feuil2").Rows(r).Delete shift:= xlup 'NOK
Sheets("Feuil3").Rows(r).Delete shift:= xlup 'NOK
End Sub