Equisys technical notes

Technical guidance, explanations and fixes for our products

PRB: An error occured while creating the add-in control for "Equisys Zetadocs CaptureAddin, PublicKeyToken..." in Factbox



This Zetadocs technical note applies to:

  • Zetadocs Delivery and Capture version 11.1 and older
  • NAV 2018, Business Central 14 and older versions
  • Windows 10


After installing Zetadocs for NAV on a client with Windows 10, the factbox shows the following error:


Zetadocs cannot load the factbox and the following error is shown when opening a page with the factbox:

"Could not load file or assembly "Unity.Abstractions""



This is caused by a 3rd party software that has added to the GAC folder one of the Unity.Container dll that Zetadocs uses, but it hasn't added the dependency of this dll, Unity.Abstraction. As the Unity.Container is in the GAC, windows searches for the Unity.Abstraction into the GAC as well and does not search into the Zetadocs folder anymore, leading to the dll being not found and the error seen.

The GAC folder is usually located in C:\Windows\Microsoft.NET\assembly\GAC_MSIL\Unity.Container\v4.0_5.11.8.0__489b6a ccfaf20ef0.


Running the following Snippet in PowerShell will add the Unity.Abstraction.dll into the GAC alongside the Unity.Container.dll. 

 $dllpath = c:\path\yourdll.dll [System.Reflection.Assembly]::Load("System.EnterpriseServices, Version=, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a") $publish = New-Object System.EnterpriseServices.Internal.Publish $publish.GacInstall($dllpath) 


Solved with the workaround described in the Resolution

Last updated: 29th June 2021 (EG) 

Keywords: Client, Control Addin, The system cannot find the file specified

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