Blacklisted from

I need a solution


My client is unable to send any emails to recipients that use the Messagelabs Filtering system.

We use Office 365 and they are coming back clean on all the spam blacklists I’ve tried, including Symantec’s.

The bounceback message we receive is:

550 5.0.350 Remote server returned an error -> 553 Message filtered. Refer to the Troubleshooting page at; for more;information. (#5.7.1)

Please, could someone help remove us from this blacklist? It’s causing so much trouble for both my client and me! I don’t want to post the domain in this post, but if someone from Symantec needs it, please ask!





Leave a Reply