private void button1_Click(object sender, EventArgs e) { try { sConn = " Provider=Microsoft.ACE.OLEDB.12.0 ; Data Source = finalprojectC#.accdb"; OleDbConnection dbConn = new OleDbConnection(sConn); dbConn.Open(); sql = "SELECT * FROM Customer_Profil WHERE email= '"+textBox1.Text+"'and Password='******'"; OleDbCommand dbCmd = new OleDbCommand(); dbCmd.CommandText = sql; dbCmd.Connection = dbConn; //Create a dbreader object dbReader = dbCmd.ExecuteReader(); while (dbReader.Read()) { count = count + 1; if (count == 1) { BookCatalog B1 = new BookCatalog(); B1.Show(); } else { MessageBox.Show("you need to sign up to buy, we can't find your account"); } } dbReader.Close(); dbConn.Close(); } catch (System.Exception exc) { label8.Text = exc.Message; } }