Hi, I was trying to figure out why the "program update check" does not work (same with the "registration code" check), and had this exact issue: Unable to resolve host name
What I found out, is that the Directory Opus decided to use a proxy server, that I had once set up on Windows manual proxy, even though I had it turned off already.
Disabling it in Opus finally makes the update checks work, but for some reason it's a default setting - "Factory reset page" turns it back on, including restoring the proxy server IP address, even if I clear it in Windows.
At the same time, if I change the address in Windows, factory reset grabs the new address, so I would assume it simply ignores the on/off switch setting?
So I guess the only question would be: is it something intended, a bug, or a unique issue with my machine?
(the last option is not out of the question, I do have a cursed PC, I think I need to hire an exorcist one day 
)