Old Javascript button

Javascript Button

{ !REQUIRESCRIPT("/soap/ajax/31.0/connection.js") }

var myquery = "SELECT Id, Name, Sent_to_Epicor__c, Contact_ID_Lookup__c FROM Opportunity WHERE Id = '{!Opportunity.Id}' limit 1";

result = sforce.connection.query(myquery);
records = result.getArray("records");

var myOpp = records[0];
var updateOpp = new Array();

var confirmMsg = 'We are in the process of sending your quote to Epicor! Please note: this quote has only been successfully posted to Epicor once the Epicor ID and Date Created In Epicor fields are populated in the Salesforce Opportunity.'

if (myOpp.Required_Opp_Fields_To_Quote__c == 'false') {
    alert('Please check the required fields before quoting');
}
else {
    myOpp.Sent_to_Epicor__c = true;
    updateOpp.push(myOpp);

    result = sforce.connection.update(updateOpp);

    if (result[0].getBoolean("success")) {
        alert(confirmMsg)
        window.location = "/" + "{!Opportunity.Id}";
    } else {
        alert('Could not Export : ' + result);
    }
}