Response.Write不能用了解决方案

Response.Write不能用了
我用了AJAX后，原来对的Response.Write不能用了！
错误提示如下：
Sys.WebForms.PageRequestManagerParserErrorException:The   message   received   from   the   server   count   not   be   parsed.Common   causes   for   this   error   are   when   the   response   is   modified   by   calls   to   response.Write(),response   filters,HttpModules,or   server   trace   is   enabled.
Details:Error   parsing   near   ' <script   language=jav '.
大家帮帮我吧~~~！


[解决办法]
楼主可以使用这一句

ScriptManager.RegisterStartupScript(this, this.GetType(), "alert1 ", "alert( '请选择联系人! '); ", true);