Normally, whenever a form is posted backed, the password field will clear. But we dont want it to do that.
In that scenario, we can add a little bit of code will avoid the issue.
Retain Password In VB.NET
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If IsPostBack Then
If Not String.IsNullOrEmpty(txtPassword.Text.Trim()) Then
protected void Page_Load(object sender, EventArgs e)
There are many other methods also to retain values between postback, whether it is password or any field value stored in any control i.e. viewstate, session, etc
However retaining password is considered to be security hole so it is not preferable to retain password between post backs.