I was able to see my delivery pipeline. I executed a job, from the pipeline and after that the pipeline would not show up. It keeps showing "Error communicating to server! Internal Server Error"

The stacktrace shown on page, when http://server:port/jenkins/view/JOB_NAME/api/json is clicked is attached as StackTrace.txt

The server log localhost.<<date>>.log shows some more details and is attached as ServerLog