When you create a SharePoint Document Library with a Lookup required column, and you generate SmartObjects and Forms for the Document Library, uploading a document to SharePoint results in an error or not being able to select a value from the Lookup List.
The following error might occur: “No item exists. It may have been deleted or renamed by another user”.
After installing the Fix Pack, you must activate your SharePoint Site from the K2 App on the site itself. It is important not to activate from the Apps Catalog. You will also have to clear the browser cache.