摘要： 今天去服务器安装了个.net 4.0 framework（原本有1.0和2.0的）,配置好站点后，选择版本为4.0，访问出错，错误代码如下Server Application Unavailable The web application you are attempting to access on this web server is currently unavailable. Please hit the "Refresh" button in your web browser to retry your request. Administrator Note: A 阅读全文