TFS API – WorkItemStore is null and throws NullReferenceException - Init

<body> <h1>TFS API – WorkItemStore is null and throws NullReferenceException</h1> In the last weeks I wrote a migration tool to migrate test cases from Rally to Team Foundation Server. This tool is deployed to a server and runs as a Windows Service. After I made a small update to this tool suddenly my tool stopped working. My log file gave me the following error: Error [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=osnabrugge.wordpress.com&blog=14364801&post=213&subd=osnabrugge&ref=&feed=1" width="1" height="1" /> </body>