New answers tagged bonjour
The solution is to edit the main.cf file in /etc/postfix, and change the myhostname = xxx-com.local line to myhostname = xxx.com. OS X Server appears to honor this change, and not attempt to change it back. However, in my opinion, OS X Server should not have chosen such an absurd default value.
Bonjour is installed on Windows alongside iTunes or iCloud Control Panel. If you have either of these it is expected to be found to be installed. Bonjour can also be required by other programs or installed separately, so it's existence is not too unusual.
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