Hey y'all,
in versions 1.15 and 1.16 i was able to set our DAG as the hostname for fetching emails, so in case one of the exchange servers was offline, it would not have an impact on the system. In 1.17 i get this error however:

As soon as i change the hostname to one of our exchange servers, it saves without problem. Of course, it's not that big of an issue, considering that our exchange servers shoud hopefully not go offline, but it was nice to have, not having to worry about this.