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Home > Success Center > Orion Platform > Orion - Knowledgebase Articles > Orion Web server error: Could not load type 'System.ServiceModel.Activation.HttpModule' from assembly

Orion Web server error: Could not load type 'System.ServiceModel.Activation.HttpModule' from assembly

Created by Kevin Twomey, last modified by MindTouch on Jun 23, 2016

Views: 1,839 Votes: 1 Revisions: 5


This article provides brief information and steps to resolve the following error after the session on the main or additional web servers:

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



All NPM versions


The error occurs when there are multiple versions of the .NET Framework on the computer that is running IIS
and IIS was installed after .NET Framework 4.0 or before the Service Model in Windows Communication Foundation (WCF) was registered.


Register the correct version of ASP.NET with ASP.NET IIS Registration Tool (aspnet_regiis.exe).

1. Open the command prompt with elevated rights (Run as Administrator).

2. Change the directory to the following: 

%WINDIR%\Microsoft.NET\Framework\v4.0.30319 or%WINDIR%\Microsoft.NET\Framework64\v4.0.30319

3. Enter the following command:

aspnet_regiis.exe -iru

Console output:
         Microsoft (R) ASP.NET RegIIS version 4.0.30319.17929
    Administration utility to install and uninstall ASP.NET on the local machine.
    Copyright (C) Microsoft Corporation. All rights reserved.
    Start installing ASP.NET (4.0.30319.17929).
     Finished installing ASP.NET (4.0.30319.17929).



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