if (!txtUsername.Equals(null) && !txtPassword.Equals(null))
            {
                string constring = @"Provider = Microsoft.ACE.OLEDB.12.0; Data Source = " + System.Environment.CurrentDirectory + "../../../res/Coursework.accdb";

                String username = txtUsername.Text;
                String password = txtPassword.Text;
                Boolean admin = chbAdmin.Checked;

                string cmdText = "insert into tblUsers (username, password, admin) Values(@username, @password, @admin)";
                using (OleDbConnection con = new OleDbConnection(constring))
                using (OleDbCommand cmd = new OleDbCommand(cmdText, con))
                {
                    con.Open();
                    cmd.Parameters.Add("@username", OleDbType.VarChar).Value = username;
                    cmd.Parameters.Add("@password", OleDbType.VarChar).Value = password;
                    cmd.Parameters.Add("@admin", OleDbType.Boolean).Value = admin;

                    cmd.ExecuteNonQuery(); //crashing here with syntax error in the insert statement
                    MessageBox.Show("Data Added");
                }
            }