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UPDATE: The block has been removed, thanks to MessageLabs for sorting this out with us. We now know the campaign that was the cause and are following up with that customer. Emails will no longer be bounced by MessageLabs because of this block (though normal content filtering still may apply).

Over the last few days we identified an unusual number of bounces for some customers’ campaigns, and discovered that some end recipients who were using MessageLab (Symantec’s email filtering service) were not getting emails from our servers.

Our deliverability team responded immediately to find out why the bouncing was happening, and to request a delisting. These kinds of listings can sometimes happen if a particular campaign triggers too many complaints, or is flagged by some heuristic filters, but generally they are very short term and easily resolved.

In this case, it is taking much longer than expected to get back to normal service. We have escalated this issue to Director level with Symantec, and they are working with us now to make sure that the original cause is dealt with appropriately, and that all our other email will be able to be delivered normally.

We’re sorry if you or your clients have had your campaigns affected by high bounce rates. Please rest assured this is something we take really seriously and we’re already working on improvements that would reduce the impact of any similar occurrence in the future.

Who is affected?

If the subscribers on your lists use MessageLabs, and they have not whitelisted our servers in any way, they may currently be bouncing your emails back. In your reports it will show as “Mail Block: General” (though not every instance of a general mail block is due to this issue). MessageLabs seems to be much more used in Australia and NZ, and in financial institutions particularly, so that could be an indicator.

What can you do right now?

If your emails are being bounced by certain domains, and you suspect this is the problem, the immediate solution is to ask the recipient to contact MessageLabs and ask for a whitelisting to get the email they opted-in to. That will fix the problem right away for that specific domain, while we work on sorting out the root issue.

Compensation for bounced emails

If you or your client have been affected, contact us via support with the details of client and campaign, and we will take a look and give you sending credit so you can resend those emails once it is clear at no cost.

We’re working on getting this fixed up as soon as we possibly can, and we appreciate your patience. We’ll update this post once we have more information for you.

This blog provides general information and discussion about email marketing and related subjects. The content provided in this blog ("Content”), should not be construed as and is not intended to constitute financial, legal or tax advice. You should seek the advice of professionals prior to acting upon any information contained in the Content. All Content is provided strictly “as is” and we make no warranty or representation of any kind regarding the Content.
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