Hi there I think I had this issue, it was on a server 2008 box, so opened up a load of ports see below, and that seemed to sort it:
[h=4]How can I run UniFi Controller on different ports[/h]
By default, UniFi controller runs on these ports
unifi.shutdown.port=8081 (for management purpose)
unifi.http.port=8080 (device inform)
unifi.https.port=8443 (controller UI / API)
portal.http.port=8880 (portal redirect port for HTTP)
portal.https.port=8843 (portal redirect port for HTTPs)
unifi.db.port=27117 (local-bound port for DB server)
