SharePoint – Workflow Event manager error

December 12, 2013

SharePoint Workflow – On Event Change issues !!

In a custom SharePoint Application we encountered the problem that a Workflow connected to a list.

Which was part of the Custom SP application was not starting based on a ON CHANGE event.

Every time we changed the record we saw this in the ULS.

Event manager error: That assembly does not allow partially trusted callers.


Solution is to go the the %windir%\assembly Directory and Drag & Drop the DLL in there. This will register them without the need of the GacUtil.exe


Do a IISReset and test again.

It it did not solve the issue you need to go a more insecure approach but more effective for sure.

Open the IIS Manager go to your Web Application, right click and choose Explore.


You will end up in the correct folder where you can pick up the web.config file.

Find this entry :

<trust level=”WSS_Custom” originUrl=”” />

And change “WSS_Custom” to “Full

Enjoy !