McAfee Spam Filter Causing Illegimate Bounce

[Chris_Vanderma1]

Some of our contacts with legitimate email addresses are bouncing getting the following error:

551 Mailhost is on our global block list. See http://mcaf.ee/5xxhelp

It seems Marketo's IP was temporarily blocked by McAfee. This leads me to two questions:

1. Has anyone else encountered this? Can any action be taken to counter this?
2. Now I have contacts with Email Suspended marked true. Will Marketo try again to send to them later? If rejected again will they become Email Invalid?

Thanks in advance!

[Kenny_Elkington]

Hi Chris,

We take appropriate action internally to followup to any blocks on Marketo IP addresses, so there should be no requirement for action on your side unless we reach out to you.  Regarding your second question, Email Suspended is a temporary 24-hour block, the field will stay marked true, but the block only lasts for 24 hours after the most recent Email Suspended Date. Email invalid will only be marked if a bounce message is received which indicates that the target address is no longer valid, or is inactive.

[Anonymous]

Occasionally this will happen, due to the fact that we share mailserver IPs with other Marketo users (you may be able to request a dedicated IP after a time) - there's nothing you can do as far as I'm aware, other than try again at a later date. Email Suspended lasts for 24 hours, and Marketo can try to send again after this period (see https://community.marketo.com/MarketoArticle?id=kA050000000L3F2CAK). If email suspended happens enough, it may be set to Invalid automatically, but I'm not 100% sure about this.