This has most probably to do with firewall settings (http-listener settings could also be a problem - but only if you have changed the default values).
For example most company firewall settings prevent you to access port 8080 from a remote host. Also the host you want to access might not be accessible from outside your company network. Most probably your admins do not want to change these settings (and rightly so). A VPN would be a possible solution.
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