Ok,
When you start tests with Jenkins, all Reports will be stored in e.g. /home/dev/jenkins-workspace/workspace/projects/Reports/
So, in HTML Publisher Plugin you need to set
HTML directory to archive: Reports/
Index pages: *.html
You can also test to set that last value with following form: .html, //Report.html, ///Report.html (I use that when I need to run Test Suites Collections, they store Reports in other folders).
If you don’t see content of reports (but you see files), you need to enable css for html publisher plugin (search in google, first/second result for stackoverflow has the resolution)