Mailings from our servers and containing some text blocked

We are and we are experiencing a problem due to what seems to be a set of rules in Symantec Email Security. We’ll explain the situation here.

Our product is an online email platform like Mailchimp, targeted at sending out press release emails for mainly corporate clients. The goal is to reduce spam towards email recipients by maximizing relevance of the sent news releases. So the fact that our clients use our product for their press releases, should improve deliverability. Many of our clients use Symantec’s security software in their email clients.

The problem now, is that Symantec seems to block or blacklist emails sent from our email servers. The software even blocks emails that merely contain “” in both headers and email content. This is causing us major damage and is endangering us as a business. Obviously, also Symantec’s clients are suffering from this, as their press releases cannot be delivered because of this false positive in Symantec’s source code. We have been able to reproduce this by sending out emails with and without containing references to ‘’ from personal Gmail accounts.

All emails sent from our product, are sent from IP The IP is not blacklisted, as can be checked here:

Another possibility could be that our mail server is marked as a spamming threat, even though we are not blacklisted. Please help us out. Thank you very much.


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