Hornetsecurity offers the possibility to setup domains including umlaut. The domains will be added through the Control Panel using the tab “Management > Domains > Alias Domains”.

For the system to be able to interpret the umlaut, it will need to be converted to an ACE-String. You will find a converter from the following website:


You will need to add the converted domain to the Control Panel. Adding a domain including an umlaut into the system will result in declined emails, as the spam filter will not be able to assign the incoming emails to the appropriate customer.

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