I have no idea why after Jenkins is updated to version 1.591 (Ubuntu Server 12.04), the originally correctly set up reverse proxy now becomes broken. My current setting is e
I was faced with this issue with Jenkins as a Windows Service Package.
According to their wiki:
Make sure the Jenkins URL configured in the System Configuration matches the URL you're using to access Jenkins.
To reach the System Configuration:
Ensure that port value matches with the port value set in the
section of the jenkins.xml file located in the Jenkins folder on your machine.