win10环境已有.net4.5以上版本，IIS无法访问站点，需要安装.net4.5，aspnet_regiis.exe -i命令无法安装.net4.5
利用dism工具依次执行下面命令安装
dism /online /enable-feature /featurename:IIS-ISAPIFilter dism /online /enable-feature /featurename:IIS-ISAPIExtensions dism /online /enable-feature /featurename:IIS-NetFxExtensibility45 dism /online /enable-feature /featurename:IIS-ASPNET45