Symptoms

Getting the following error when workflow get to the activity that need to execute SharePoint V2 Service Broker:
“The Request failed with HTTP status 401: Unauthorized ServiceName:… ServiceGuid:…”

 

Diagnoses

When browsing to the SharePoint site from K2 Server logged in as K2 Service account, the browser would prompt for credential. This is the reason that K2 Service could not make the call to the Web Service on the SharePoint server.
 

Resolution

Resetting Internet Explorer on the K2 Server resolved the issue.