Could not load type 'System.ServiceModel.Activation.HttpModule' from assembly 'System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b

"Could not load type 'System.ServiceModel.Activation.HttpModule' from assembly 'System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'"

出现这个错误的原因是：先安装了.Net Framework 4 后安装IIS 。

This error can occur when IIS is installed after installing .NET Framework 4, or if the 3.0 version of the WCF Http Activation module is installed after installing IIS and .NET Framework 4.

To resolve this problem, you must use the ASP.NET IIS Registration Tool (Aspnet_regiis.exe,) to register the correct version of ASP.NET. This can be accomplished by using the –iru parameters when running aspnet_regiis.exe as follows:

aspnet_regiis.exe的路径如下所示：

C:\Windows\Microsoft.NET\Framework\v4.0.30319\aspnet_regiis.exe

aspnet_regiis.exe -iru