I'm upgrading to ExtJS 5 and can't solve this issue. I've got a function that manages everything after the login and loads store after login with the new parameters from login.

```
...
Ext.create('MyApp.store.MainStore').load({
        params: {
            auth: sessionStorage.authSessionId,
            hostname: sessionStorage.hostname
        },
        callback: function(records, operation, success) {
            //some callback
        }
})
...

```

However this loads the store, but without parameters, which causes an error on server side.
My store definition:

```
Ext.define('MyApp.store.MainStore', {
    extend: 'Ext.data.TreeStore',
    storeId: 'MainStore',
    autoSync: false,
    autoLoad: false,

    proxy   : {
        type : 'ajax',
        url  : '/menu',
        reader: {
            type: 'json',
            rootProperty: 'children',
        },
        listeners : {
                exception : function(proxy, response, operation) {
                    //exception handling
                }
            }
    },
    fields: ['labelText','dbName','corpName','isLeaf', 'page']

});

```

Any suggestions?
Thanks for any help.