Microsoft JScript 运行时错误: 'Sys' 未定义 解决方案
使用ajax的scriptmanager控件是产生此错误的情况,解决方案是向项目所在webconfig 的<system.web>节点下添加如下代码:

1 <httpHandlers>
2 <remove verb="*" path="*.asmx"/>
3 <add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
4 <add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" validate="false"/>
5 </httpHandlers>
6
7 <httpModules>
8 <add name="ScriptModule" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
9 </httpModules>