Why XI's SLD does not show?


Why XI's SLD does not show?
We have an XI (PI7) system, when trying to access the SLD:
after hitting "enter", it changes to
Then the browser shows blank and the bottom message bar shows
We have the FQDN maintained in the hosts file on the testing PC.
How to bring it up?
Thanks a lot!!
  When you access the Java Stack through the internet browser, can you get to any functionality (something like http://<FQDN>:50000/index.html)?  Is this something new or did this work in the past but is now not working?  Is this a new install, upgrade or have other changes been applied recently?
  Thanks for the follow-up information to let us all know the context of the problem.
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