edit Form Results in Error

Question

I cant find a glue for that. Trying to edit a Listitem in the Browser , I get an Error the Log says:

   File Not Found: C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\Template\Layouts\EditingMenu\SiteAction.xml
System.ArgumentNullException: Der Wert darf nicht NULL sein.  Parametername: s    bei System.IO.StringReader..ctor(String s)     bei System.Xml.XmlDocument.LoadXml(String xml)     bei Microsoft.SharePoint.Publishing.Internal.WorkflowUtilities.FlattenXmlToHashtable(String strXml)     bei Microsoft.SharePoint.Publishing.Internal.WorkflowUtilities.DoesWorkflowCancelWhenItemEdited(String associationXml)     bei Microsoft.SharePoint.Publishing.WebControls.ConsoleDataSource.EnsurePageNotInLockingWorkflowIfInEditMode()     bei Microsoft.SharePoint.Publishing.WebControls.ConsoleDataSource.OnPreRender(EventArgs e)     bei System.Web.UI.Control.PreRenderRecursiveInternal()     bei System.Web.UI.Control.PreRenderRecursiveInternal()     bei System.Web.UI.Control.PreRenderRecursiveInternal()     bei Sy... 489b3ebb-eb93-4172- SharePoint Foundation           Runtime                         tkau    Unexpected  System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)  

The Xml is in Place and Edit Forms for Other Lists in the same Web are working well ... Even Tried to make a new Editform ( and iisreset etc..)

Any Hint would be helpfull

Thanks Lars

Answer 1

Do you have any custom code/workflow setup for that custom list?

Answer 2

Thank you for pointing me in the right direction In fact there was a Workflow for Disposition Approval attached to the Element Content type, not shure who placed it there, but anyways the Tasks could be found at the List. The Workflow was nerly invisible to me. The Error is odd something I didnt expected

Lars