How to connect to Secure MS Access Database in VB.Net ?

Question

I used the following code to connect with a Access Database :

Public Con As System.Data.OleDb.OleDbConnection = New System.Data.OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=.\\DemoDatabase.accdb")

It works fine.
But when I make the database secure (password protected), it doesn't connect.
username = did not asked by Access
password = dbpasscode
Please help ....