Phenomenon:
When you access AEM or the Appeon web application, you may run into the error message “Could not load type from assembly System.ServiceModel.Activation.HttpModule System.ServiceModel, Version = 3.0.0.0, Culture = neutral, PublicKeyToken = b77a5c561934e089.” More details please refer to the article posted at: http://support.microsoft.com/kb/2015129
Cause:
This issue occurs because the Applicationhost.config file for Windows Process Activation Service (WAS) has the following section defined, and this section is incompatible with the .NET Framework 4.0:
<add name="ServiceModel" type="System.ServiceModel.Activation.HttpModule, System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" preCondition="managedHandler" />
This section should be defined as follows:
<add name="ServiceModel" type="System.ServiceModel.Activation.HttpModule, System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" preCondition="managedHandler,runtimeVersionv2.0" />
Note: You can find the Applicationhost.config file in the following location:
%windir%\system32\inetsrv\config
Solution:
To resolve this issue, run the following command line:
aspnet_regiis.exe /iru
The Aspnet_regiis.exe file can be found in one of the following locations:
%windir%\Microsoft.NET\Framework\v4.0.30319
%windir%\Microsoft.NET\Framework64\v4.0.30319 (on a 64-bit computer)