I have strange problem. My application is using Windows Workflow Foundation. It is simple app that creates requests and then other presons accepts/denies these requests. Everything was working very fine until my client took application to other servers (app and db). From this time WF instances are created in DB but when app tries to fire event to WF instance it strikes exception: "Event "EventName" for instance id "instanceGUID" cannot be delivered". What went wrong? Any suggestion where to start find the problem?