On March 1st we brough the spam filtering servers located in the EU (Frankfurt) online. This means that we’ll have greater capacity and redundancy for your mail, you can read our entire post about our multi zone spam filtering approach.
However if you are currently firewalling your mail server to only accept mail from DuoCircle IP pool you will need to add these IP’s to your white list in order for your email to be delivered correctly:
Spam Filtering Exclusively in the European Union
If you are an EU customer and would like your messages to only be filtered in the Europe you can update your MX record to:
Spam Filtering Exclusively in the United States
Conversely if you’d prefer that you mail never goes to the EU and stays within the United States of America you can use this MX record: