Salesforce JavaScript未终止字符串常量错误

我使用JavaScript在Salesforce中创建了一个按钮，它将查询（自定义对象）转换为注册（Contact）。该按钮适用于我自己和我在相同配置文件和权限上登录的任何测试用户，但我的一个用户在使用该按钮时会报告错误。

错误如下：

'分层字符串常量'

我在按钮中使用的代码如下：

{!REQUIRESCRIPT('/soap/ajax/27.0/connection.js')}
alert('Migration in progress, this page will refresh once it is complete. Please click ok, Please DO NOT press this button again');
if ('{!Enquiry__c.Surname__c}' != ''){
if ('{!Enquiry__c.Client_if_already_on_the_system__c}' == ''){ 
var Reg = new sforce.SObject('Contact'); 
Reg.FirstName = '{!Enquiry__c.First_Name__c}'; 
Reg.LastName = '{!Enquiry__c.Surname__c}'; 
Reg.Gender__c = '{!Enquiry__c.Gender__c}'; 
Reg.MailingStreet = '{!Enquiry__c.Address__c}'; 
Reg.MailingPostalCode = '{!Enquiry__c.Post_Code__c}'; 
Reg.MailingCity = '{!Enquiry__c.City_Town__c}'; 
Reg.MailingState = '{!Enquiry__c.County__c}'; 
Reg.HomePhone = '{!Enquiry__c.Home_Number__c}'; 
Reg.MobilePhone = '{!Enquiry__c.Mobile_Number__c}'; 
Reg.Email = '{!Enquiry__c.E_mail__c}'; 
Reg.Lastest_Enquiry__c = '{!Enquiry__c.Id}'; 
result = sforce.connection.create([Reg]); 
if (result[0].success == 'true'){ 
alert('A new Registration with the name - ' + Reg.FirstName + ' ' + Reg.LastName + ' was successfully created, Please DO NOT press this button again as duplication''s will be created, Your client will be automatically connected to this enquiry'); 
javascript: document.location.reload(true); 
} 
}else{ 
alert('Cannot Migrate to Registration as there is already a Client connected to this Enquiry'); 
}
}else{
alert('Cannot Migrate to Registration as Surname is blank!'); 
}

用户告诉我他们正在使用IE作为浏览器，我已经在Chrome、Edge和最新的IE上测试了该按钮。有人知道怎么了吗？