This is a continuous issue that has been ongoing for over 4 months now.
Sending emails to any clients that are using MessageLabs is bouncing back with a 553 error. We have contacted Symantec directly only to be told the only way to fix the issue is to buy their products so we can submit a ticket to support. We have sent multiple emails to the “investigation” email address only for them to either bounce back from 553 error (Ironic right), or receive no response at all from the support team.
We have also had a client raise a ticket on our behalf, which has been unsuccessful with Symantec giving no reason why they wouldn’t resolve the issue.
For anyone considering these products, they are going to end up costing you time and money when clients/customers are unable to send you emails until these issues are fixed I would reconsider your options.
Sending IPs are below, If anyone can help it would be truly appreciated.