Imports System.Data.OleDb
Public Class Form1

    Private Sub Form1_Load(...)
        Dim dbCon As OleDbConnection
        Dim dbCmd As OleDbCommand
        Dim dbRead As OleDbDataReader

        dbCon = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\My.accdb;Persist Security Info=False;")
        dbCon.Open()  

        dbCmd = New OleDbCommand("SELECT * FROM CITY", dbCon)
        dbRead = dbCmd.ExecuteReader
        Do While dbRead.Read
            MsgBox(dbRead(1))
        Loop
    End Sub
End Class

    Private Sub Form1_Load(...)
        Dim dbCon As OleDbConnection
        Dim dbCmd As OleDbCommand
        Dim dbRead As OleDbDataReader
try
        dbCon = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\My.accdb;Persist Security Info=False;")
        dbCon.Open()  
catch ex as exception
msgBox(ex.Message, vbOkOnly, "Error During dbCon.Open()")
return
End Try

        dbCmd = New OleDbCommand("SELECT * FROM CITY", dbCon)
        dbRead = dbCmd.ExecuteReader
        Do While dbRead.Read
            MsgBox(dbRead(1))
        Loop
    End Sub

Dim DBName as String = "c:\path_of_db\dbname.dbext"
Dim ConString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & DBName & ";User ID=Admin;Password="

dbCon = New OleDbConnection(ConString)