Why isn't the spam filter blocking email addresses that are listed on the blocklist?

Environment:

Incoming Email, Spam Filtering, SMTP forward
Oracle B2C Service

Issue:

I have added many email addresses to the spam tool blocklist, but emails are still coming through to Oracle B2C Service.

Resolution:

The most common reason for which blocked emails would reach your Oracle B2C Service site are because the email was routed through the spam filters for a different datacenter than the site's current datacenter.  The most common reasons emails are processed first by a different datacenter include: 

1. Having SMTP forwarding to Oracle-hosted mailboxes using incomplete domain or referencing older (typically decommissioned) datacenters
2. Mailbox Reply-To and / or Envelope From address using incomplete domain or referencing older (typically decommissioned) datacenters.

When setting up SMTP forwarding on your external mail server to redirect emails into a hosted mailbox, it is important to specify the full email address which includes the POD your site is currently hosted on, like support@mailph.custhelp.com (for sites on PH datacenter). The forwarding and redirect rules should also be updated after any datacenter migration.  

If not using your own domain for a mailbox's Reply-To Address and / or Envelope From / Bounce Address, then ensure the full domain with the current 2-letter datacenter designation is used.

You can find your 2-letter Data Center abbreviation on the Site Information page.

Another reason an email may not be blocked by the spam tool is if contacts send emails with a Reply-To address that differs from the email's "From" or "Sender" address. Before adding a contact's email address to your spam tool blocklist, be sure to view a recent email header for an undesired email and add the "From" address to the blocklist and not the "Reply-to" address.

Cause:

When emails are sent to the full address of the hosted mailbox for the site's current datacenter location (e.g., support@mailph.custhelp.com for sites in PH datecenter), the emails are processed though the proper spam filter. 

• If the full address is not used (e.g., support@custhelp.com), email will be processed through the FT pod and use the FT pod spam filter. 
• If the full address refers to a decommissioned datacenter (e.g., support@mailva.custhelp.com), email will be processed in an active datacenter based on our internal routing, but this may not coincide with your site's current datacenter location. 

The spam filter in the datacenter that processed the email may not have been configured, depending on which datacenter received the email and whether it needed to be routed to another datacenter where the site currently resides.

By default, when you use the Spam Management Tool using the steps in the following answer, you are modifying the Safelist and Blocklist for the datacenter where your site is currently hosted. 

Answer ID 11713: Managing Spam Messages

 Techmail will create and associate contacts based on an email's reply-to address if it is different than the "from" or "sender" address (see Answer ID 6677: Email address used for contacts created from email messagesAnswer ID 6677: Email address used for contacts created from email messages ). However, the spam filter checks an email's "Sender" and "From" address and not the "Reply-to" address. 

For more details about SMTP forwarding or finding the datacenter abbreviation, please see:
Answer ID 6404: Always use the full domain name in mailbox reply-to addresses
Answer ID 1272: How can we have our company's domain name in the "Sent" email address instead of the "@custhelp.com"? 

To easily check email header, please see:
Answer ID 1595: Including email headers for incidents created from email