MessageLabs/Symantec cloud has started blocking all mail from my system without reason. I really need help with this and hope that someone from Symantec can help.
We cannot send to any clients (of which there are many) that are using MessageLabs to filter their mail. The bounce back we get is:
[216.82.250.19] #<[216.82.250.19] #5.0.0 smtp; 5.3.0 - Other mail system problem 553-'Message filtered. Refer to the Troubleshooting page at\nhttp://www.symanteccloud.com/troubleshooting for more\ninformation. (#5.7.1)' (delivery attempts: 0)> #SMTP#
Our mail exchangers are not listed on any black list and have a very good reputation score.
Our mail exchangers are:
mail1.hilcotrading.com 50.204.121.49
mail2.hilcotrading.com 159.100.210.19
Please help! Thank you so much.