If you are having problems going to the Unit 4 website and you know it is a DNS issue, you can use the IP numbers directly:
http://18.104.22.168/ [I just tested it]
How do you know if it is DNS? In Chrome, you will see a message like:
Error 105 (net::ERR_NAME_NOT_RESOLVED): Unable to resolve the server's DNS address.
UPDATE: 1:04 pm – Apparently, ICN (“the outside resolver”) had a problem this morning. As of now, the problems have been fixed.