Private Sub TextBox1_Exit(ByVal Cancel As MSForms.ReturnBoolean)
Dim Msg$, x As Boolean
Msg = "Be careful: No modification requested on the folios" & vbCrLf & _
"Put the desired change or cancel the action"
With TextBox1
x = IsNumeric(.Value) And InStr(1, .Value, "-") = 0
If x Then
CommandButton2.Enabled = True
Else
Cancel = True
.Value = ""
.SelStart = 0
MsgBox Msg
CommandButton2.Enabled = False
End If
End With
End Sub