Worksheet Change Event Wrongly Trigger

Try This...

Private Sub Worksheet_Change(ByVal Target As Range)
Dim cell As Range
On Error GoTo Deb
Application.EnableEvents = False

For Each cell In Target
    If Target.Column >= 2 And Target.Column <= 9 And WorksheetFunction.CountBlank(Range("B" & Target.Row & ":I" & Target.Row)) = 8 Then
        Range("SC" & Target.Row).Resize(Target.Rows.Count, 26).ClearContents
    End If
Next cell

Deb:
    Application.EnableEvents = True
End Sub