Error message when server returns undefined error. If you do not like default message, you are welcome to define your own. let grid = new w2grid({ name : 'grid', msgAJAXerror : 'Uncaught AJAX error', columns: [ { field: 'recid', text: 'ID', size: '50px' }, { field: 'lname', text: 'Last Name', size: '30%' }, { field: 'fname', text: 'First Name', size: '30%' }, { field: 'email', text: 'Email', size: '40%' }, { field: 'sdate', text: 'End Date', size: '120px' } ], records: [ { recid: 1, fname: 'John', lname: 'doe', email: 'vitali@gmail.com', sdate: '1/3/2012' }, { recid: 2, fname: 'Stuart', lname: 'Motzart', email: 'jdoe@gmail.com', sdate: '2/4/2012' }, { recid: 3, fname: 'Jin', lname: 'Franson', email: '--', sdate: '4/23/2012' }, { recid: 4, fname: 'Susan', lname: 'Ottie', email: 'jdoe@gmail.com', sdate: '5/3/2012' }, { recid: 5, fname: 'Kelly', lname: 'Silver', email: 'jdoe@gmail.com', sdate: '4/3/2012' }, { recid: 6, fname: 'Francis', lname: 'Gatos', email: 'vitali@gmail.com', sdate: '2/5/2012' } ] });