--- title: "Notification of Nettica Filtering Change | DuoCircle" description: "Commencing Monday February 15th the spam filtering system for selected Nettica customers will be upgraded." image: "https://www.duocircle.com/images/og-default.png" canonical: "https://www.duocircle.com/blog/support-issues/notification-of-nettica-filtering-change/" --- Quick Answer Starting Monday February 15, 2016, spam filtering for selected Nettica customers moves to DuoCircle. The maintenance window runs February 15 to 17\. Customers using email forwarding, gateway, and MX backup with Dyn-managed DNS migrate fully to DuoCircle's infrastructure. Hosted email customers keep their Nettica account for mailbox access but get DuoCircle filtering and a separate DuoCircle account to manage it. Technical change: the old MX (mail1.mailhostingservice.com pointing directly at Nettica) is replaced with mx.mailhostingservice.com on a separate filtering cluster, which then forwards to Nettica for hosted email or fully replaces it for forwarding, MX backup, and gateway customers. Filtering and MX backup customers restricting delivery by IP must add the DuoCircle IP space to firewall allowlists. Share [ ](https://www.linkedin.com/sharing/share-offsite/?url=undefined%2Fblog%2Fsupport-issues%2Fnotification-of-nettica-filtering-change%2F "Share on LinkedIn") [ ](https://twitter.com/intent/tweet?text=Notification%20of%20Nettica%20Filtering%20Change&url=undefined%2Fblog%2Fsupport-issues%2Fnotification-of-nettica-filtering-change%2F "Share on X/Twitter") [ ](https://www.facebook.com/sharer/sharer.php?u=undefined%2Fblog%2Fsupport-issues%2Fnotification-of-nettica-filtering-change%2F "Share on Facebook") [ ](https://reddit.com/submit?url=undefined%2Fblog%2Fsupport-issues%2Fnotification-of-nettica-filtering-change%2F&title=Notification%20of%20Nettica%20Filtering%20Change "Share on Reddit") [ ](mailto:?subject=Notification%20of%20Nettica%20Filtering%20Change&body=Check out this article: undefined%2Fblog%2Fsupport-issues%2Fnotification-of-nettica-filtering-change%2F "Share via Email") ![Notification](https://media.mailhop.org/duocircle/images/2016/02/hosted-email-server-7865.jpg) Commencing Monday February 15th the spam filtering system for selected Nettica customers will be upgraded. We initially notified you of this change on October 30th, this is a follow up message. We have opened a maintenance window from the 15th until the 17th. Additional technical information is available on our status page. The goal is to provide Nettica subscribers with the front end filtering from DuoCircle rather than relying on the spam filtering from Nettica. During this transition, email forwarding, gateway clients who’s DNS is managed by Dyn.com will be migrated completely to the DuoCircle platform and will no longer be managed on Nettica. Hosted Email users will continue with the same service but will have email filtered on DuoCircle, these customers will continue to have a nettica account for managing their email / access to their inboxes and a DuoCircle account to manage their spam filtering. **Timeline** Notifications, Week of Feb 7-14 Cut Over, Feb 15th, 18th **Technical Changes** In technical terms what we are doing is modifying the current MX record from: **mail1.mailhostingservice.com**, which points directly to the Nettica servers and we are then installing a front end filter mx.mailhostingservice.com which is a completely different set of servers. The mx.mailhostingservice.com server will then forward the email to the Nettica servers directly for Hosted Email accounts and it will replace the Nettica servers completely for email forwarding, mx backup and gateway customers. **Firewalls** If you are a filtering or mx backup customer and you are restricting delivery to your mail server by IP please update your list to include the DuoCircle IP address space. ![Brad Slavin](https://media.mailhop.org/dmarcreport/images/team/brad-slavin.jpg) Brad Slavin General Manager General Manager at DuoCircle. Product strategy and commercial lead across the email security portfolio. ## Secure your email infrastructure Protect, authenticate, and deliver. Contact our team to find the right solution. [Contact Sales](/contact/) [Explore Products](/products/) ## Related Articles [ support-issues 2m Announcing 24/7 Phone Support Aug 15, 2015 ](/blog/support-issues/announcing-247-phone-support/)[ support-issues 1m DuoCircle Increases Support Coverage Jun 1, 2015 ](/blog/support-issues/duocircle-increases-support-coverage/)[ support-issues 4m DuoCircle Infrastructure Overview Feb 18, 2015 ](/blog/support-issues/duocircle-infrastructure-overview-2/)[ support-issues 1m The DuoCircle Services Explained Mar 2, 2016 ](/blog/support-issues/duocircle-service-need/) ```json {"@context":"https://schema.org","@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com","logo":{"@type":"ImageObject","url":"https://www.duocircle.com/images/duocircle-logo.png"},"description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. 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