We need to change your password frequently from time to time from being hacked. While changing we have to enter old password and your desired new password and to confirm it we have to again enter the new password.

Program

Imports System.Data

Imports System.Data.OleDb

Public Class Form1

Dim ConnectionString As String = System.Configuration.ConfigurationSettings.AppSettings("dsn")

Dim con As OleDbConnection

Dim com As OleDbCommand

Dim oledbda As OleDbDataAdapter

Dim ds As DataSet

Dim str As String

Dim up As Byte

Private Sub btn_change_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn_change.Click

If TextBox3.Text <> TextBox2.Text Then

MsgBox("confirm password not matching with new passsword")

TextBox3.Focus()

Exit Sub

End If

Try

'If con.State = ConnectionState.Open Then

' con.Close()

'End If

con = New OleDbConnection(ConnectionString)

con.Open()

str = "select * from login"

com = New OleDbCommand(str, con)

Dim reader As OleDbDataReader = com.ExecuteReader

Do While reader.Read

If TextBox1.Text = reader("oldpwd") Then

up = 1

End If

Loop

If up = 1 Then

str = "update login set newpwd='" & TextBox3.Text & "' where oldpwd='" & TextBox1.Text & "'"

com = New OleDbCommand(str, con)

com.ExecuteNonQuery()

MsgBox("Password changed")

Else

MsgBox("Please enter correct Oldpassword and Newpassword")

TextBox1.Focus()

End If

reader.Close()

con.Close()

Catch ex As Exception

MsgBox(ex.Message)

End Try

clear()

bind()

End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

clear()

End Sub

Sub clear()

If Len(TextBox1.Text) = 0 & Len(TextBox2.Text) = 0 Then

TextBox1.Text = ""

TextBox2.Text = ""

TextBox3.Text = ""

Else

TextBox3.Text = ""

TextBox1.Clear()

TextBox2.Clear()

TextBox3.Clear()

TextBox1.Focus()

'Me.Close()

End If

End Sub

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

bind()

End Sub

Sub bind()

con = New OleDbConnection(ConnectionString)

con.Open()

str = "select * from login"

com = New OleDbCommand(Str, con)

oledbda = New OleDbDataAdapter(com)

ds = New DataSet()

oledbda.Fill(ds, "login")

DataGridView1.DataSource = ds

DataGridView1.DataMember = "login"

con.Close()

End Sub

End Class

Output