Compilation Error on an extension on Integration Studio

Hi everyone,
We create an extension in Integration Studio. In the c# project, we installed the iText7 library, through NuGet. In the principal class of the project, we extended this class LocationTextExtractionStrategy of Itext in this way: (this class is just a test)

using System;
using System.Collections;
using System.Data;
using iText.Kernel.Pdf.Canvas.Parser.Listener;
using OutSystems.HubEdition.RuntimePlatform;
using OutSystems.RuntimePublic.Db;


namespace OutSystems.NssExtensionPDF {


    public class CssExtensionPDF: LocationTextExtractionStrategy, IssExtensionPDF {


        /// <summary>
/// </summary>
public void MssAction1() {
// TODO: Write implementation for action
        } // MssAction1


    } // CssExtensionPDF


} // OutSystems.NssExtensionPDF

We compiled on Visual Studio without any error and we went back on Integration Studio and published, even here without errors.
Once published we went on Service Studio, creating a testing app and adding on this one the dependency of the project created on Integration Studio.
We got this error:

Internal Error
Compilation Error.
referencesProxy\Extension_ExtensionPDF_proxy.cs(25,22): error CS0012: The type 'iText.Kernel.Pdf.Canvas.Parser.Listener.LocationTextExtractionStrategy' is defined in an assembly that is not referenced. You must add a reference to assembly 'itext.kernel, Version=, Culture=neutral, PublicKeyToken=8354ae6d2174ddca'.
public partial class RssExtensionExtensionPDF {
bin\OutSystems.NssExtensionPDF.dll: (Location of symbol related to previous error)
State: Build References Proxy

We checked on Visual Studio that there was the reference, we don't have any clue of what this error could be. Can you help?

Outsystem Version: 11.8.10
.NET Framework 4.6.1


Can you check if " iText7 " assembly is visible in the Integration studio Resource section...


I can build it successfully 

In general your extension will be in .Net FreamWork 4.6.1. Intially I was getting the same error bcos when I tried to access the assembly from my Other dot net solution where I used the iText version was 4.7.1. That time I was unable to compile the extension. Then I change the source versiion to same as extension version 4.6.1. Now I can publish. Also check if all those dlls are included in your extension dotnet app.



Hi Sourav,
Thanks for replying.
We are actually using the last version of iText with .NET framework 4.6.1, like you showed, and all the dlls are included in the extension. We don't have any problem with publishing from Integration Studio but the error occurred when we add dependencies to our test app and re-publish it.