Hi,

If grid has locked column, grid can not restore it's state.

here is a test:

Code:
        Ext.require([
            'Ext.grid.*',
            'Ext.data.*',
            'Ext.util.*',
            'Ext.state.*'
        ]);


        Ext.onReady(function () {
            Ext.QuickTips.init();
            Ext.state.Manager.setProvider(new Ext.state.CookieProvider({
               expires: new Date(new Date().getTime()+(1000*60*60*24*7)), //7 days from now
            }));


            // sample static data for the store
            var myData = [
        ['3m Co', 71.72, 0.02, 0.03, '9/1 12:00am'],
        ['Alcoa Inc', 29.01, 0.42, 1.47, '9/1 12:00am'],
        ['Altria Group Inc', 83.81, 0.28, 0.34, '9/1 12:00am'],
        ['American Express Company', 52.55, 0.01, 0.02, '9/1 12:00am'],
        ['American International Group, Inc.', 64.13, 0.31, 0.49, '9/1 12:00am'],
        ['AT&T Inc.', 31.61, -0.48, -1.54, '9/1 12:00am'],
        ['Boeing Co.', 75.43, 0.53, 0.71, '9/1 12:00am'],
        ['Caterpillar Inc.', 67.27, 0.92, 1.39, '9/1 12:00am'],
        ['Citigroup, Inc.', 49.37, 0.02, 0.04, '9/1 12:00am'],
        ['E.I. du Pont de Nemours and Company', 40.48, 0.51, 1.28, '9/1 12:00am'],
        ['Exxon Mobil Corp', 68.1, -0.43, -0.64, '9/1 12:00am'],
        ['General Electric Company', 34.14, -0.08, -0.23, '9/1 12:00am'],
        ['General Motors Corporation', 30.27, 1.09, 3.74, '9/1 12:00am'],
        ['Hewlett-Packard Co.', 36.53, -0.03, -0.08, '9/1 12:00am'],
        ['Honeywell Intl Inc', 38.77, 0.05, 0.13, '9/1 12:00am'],
        ['Intel Corporation', 19.88, 0.31, 1.58, '9/1 12:00am'],
        ['International Business Machines', 81.41, 0.44, 0.54, '9/1 12:00am'],
        ['Johnson & Johnson', 64.72, 0.06, 0.09, '9/1 12:00am'],
        ['JP Morgan & Chase & Co', 45.73, 0.07, 0.15, '9/1 12:00am'],
        ['McDonald\'s Corporation', 36.76, 0.86, 2.40, '9/1 12:00am'],
        ['Merck & Co., Inc.', 40.96, 0.41, 1.01, '9/1 12:00am'],
        ['Microsoft Corporation', 25.84, 0.14, 0.54, '9/1 12:00am'],
        ['Pfizer Inc', 27.96, 0.4, 1.45, '9/1 12:00am'],
        ['The Coca-Cola Company', 45.07, 0.26, 0.58, '9/1 12:00am'],
        ['The Home Depot, Inc.', 34.64, 0.35, 1.02, '9/1 12:00am'],
        ['The Procter & Gamble Company', 61.91, 0.01, 0.02, '9/1 12:00am'],
        ['United Technologies Corporation', 63.26, 0.55, 0.88, '9/1 12:00am'],
        ['Verizon Communications', 35.57, 0.39, 1.11, '9/1 12:00am'],
        ['Wal-Mart Stores, Inc.', 45.45, 0.73, 1.63, '9/1 12:00am']
    ];


            /**
            * Custom function used for column renderer
            * @param {Object} val
            */
            function change(val) {
                if (val > 0) {
                    return '<span style="color:green;">' + val + '</span>';
                } else if (val < 0) {
                    return '<span style="color:red;">' + val + '</span>';
                }
                return val;
            }


            /**
            * Custom function used for column renderer
            * @param {Object} val
            */
            function pctChange(val) {
                if (val > 0) {
                    return '<span style="color:green;">' + val + '%</span>';
                } else if (val < 0) {
                    return '<span style="color:red;">' + val + '%</span>';
                }
                return val;
            }


            // create the data store
            var store = Ext.create('Ext.data.ArrayStore', {
                fields: [
           { name: 'company' },
           { name: 'price', type: 'float' },
           { name: 'change', type: 'float' },
           { name: 'pctChange', type: 'float' },
           { name: 'lastChange', type: 'date', dateFormat: 'n/j h:ia' }
        ],
                data: myData
            });


            // create the Grid
            var grid = Ext.create('Ext.grid.Panel', {
                store: store,
                columnLines: true,
                stateful: true,
                stateId: 'test123',
                columns: [{
                    text: 'Company<br>Name', // Two line header! Test header height synchronization!
                    locked: true,
                    width: 200,
                    sortable: false,
                    dataIndex: 'company'
                }, {
                    text: 'Price',
                    width: 125,
                    sortable: true,
                    renderer: 'usMoney',
                    dataIndex: 'price'
                }, {
                    text: 'Change',
                    width: 125,
                    sortable: true,
                    renderer: change,
                    dataIndex: 'change'
                }, {
                    text: '% Change',
                    width: 125,
                    sortable: true,
                    renderer: pctChange,
                    dataIndex: 'pctChange'
                }, {
                    text: 'Last Updated',
                    width: 135,
                    sortable: true,
                    renderer: Ext.util.Format.dateRenderer('m/d/Y'),
                    dataIndex: 'lastChange'
                }],
                height: 350,
                width: 600,
                title: 'Locking Grid Column',
                renderTo: 'grid-example',
                viewConfig: {
                    stripeRows: true
                }
            });
        });