vb.net datetimepicker not taking value from my.setting - vb.net

Question

I have this code to save value from datetimepicker1:
Private Sub DateTimePicker1_Validating(sender As Object, e As EventArgs) _
Handles DateTimePicker1.Validating
My.Settings.dt1value= DateTimePicker1.Value.ToString
MsgBox("before save")
My.Settings.Save()
MsgBox("after save")
End Sub
It look that it saves value in My.Settings (From Message box 1,2)
Then when closing the app and running it again; it is not loading the My.Settings.dt1value into DateTimePicker1
The code for loading is:
Private Sub main_Shown(sender As Object, e As EventArgs) Handles Me.Shown
DateTimePicker1.Value = Convert.ToDateTime(My.Settings.dt1value)
End Sub
Other controls like Textbox1 is saving and loading properly but only for DateTimePicker is not working.
I tried to change from Handles Me.Shown to Handles Me.Load but same problem.
I have another problem,
When I deploy the application and setup in windows, My.Setting.Save() not working for all controls.
I had read other similar posts and try to follow them but nothing helps.
Any tip appreciated,
Thanks in advance.

Answer 1

First check whether the value is getting saved. Use
MsgBox(My.Settings.dt1value)
instead of
MsgBox("after save").
This will ensure the value is getting saved.
MsgBox("before save") & MsgBox("after save") does NOTHING useful here
But as from your code snippet, It seems the value is getting saved.
In the form Load event write the below mentioned code and check for the output:
string DatePattern = "dd/MM/yyyy HH:mm:ss";
DateTime ConvertedDateTime;
DateTimePicker1.Value = DateTime.TryParseExact(My.Settings.dt1value, DatePattern , null, DateTimeStyles.None, out ConvertedDateTime))
Edit : About your second problem
That is because whenever you update or modify the application in any way, the My.Settings(built-in settings file) gets flushed and a new one is generated. I would suggest you to save your config file in a separate external file. NOT in My.Settings