Private Sub Text1_LostFocus()
  Dim sTemp As String
 
  sTemp = Replace(Text1.Text, ":", "")
  While Len(sTemp) < 2: sTemp = "0" & sTemp: Wend
  If Len(sTemp) = 2 Then
    sTemp = sTemp & "00"
  ElseIf Len(sTemp) < 4 Then
    sTemp = "0" & sTemp
  End If
  sTemp = Left$(sTemp, 2) & ":" & Mid$(sTemp, 3, 2)
 
  If IsDate(sTemp) Then
    Text1.Text = sTemp
  Else
    MsgBox "Error..."
  End If
End Sub

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