Issue Description

When manually adding a folder to a SharePoint Document Library and a workflow is set to start when an item is added, an error occurs. The functionality to start a workflow when adding a folder is not available, which means the workflow should not start. However, when designing a workflow in K2 Studio or K2 Designer for Visual Studio and an Item Reference is used to set a property for example “Folio”, the event receiver attempts to start the workflow, which causes the error.

Error Message

The error states that: “Microsoft.SharePoint.Client.ServerException: Cannot invoke method or retrieve property from null object. Object returned by the following call stack is null. 'File'”. This error message is displayed in K2 Workspace > Workflow Server > Error Profiles > All or K2 Management > Workflow Server > Errors > All.


  1. Ensure you have K2 4.7 installed.
  2. Download and install the K2 4.7 November 2017 Cumulative Update from K2 Partner and Customer Portal.
  3. Get the K2 4.7 November 2017 Cumulative Update FP6 from Regional Support.
  4. Install the K2 4.7 November 2017 Cumulative Update FP6 to apply the fix.
  5. When adding a new folder manually the workflow will not start.