Overview

If you are going to send bulk email you need to know something about feedback-loops or complaint loops.

What Are FBL/Complaint Loops?

Feedback (FBL) or Complaint "Loops" are mechanisms where a  recipient may file a complaint about your email with their ISP.  Then, the ISP  sends us a  generic  ARF format email  back  with  information that our system can use to make that recipient as a  complainant and also track  how many complaints are being  filed  against your mailing and subsequently "us".

1. you send an email through our system
2. user receives email and clicks on the "complaint" button their ISP has put in their email client (yahoo/aol, e.g.,)
3. ISP sends specially formatted message back to us telling us there was a complaint so you can improve the quality of your lists

Complaints must be below  2.5%  and  preferably zero.   A fully double-opted-in list should not  provide any  complaint  triggers.

Next Steps:   Setting up your FBLs:

Setting up email complaint/feedback loops (FBLs) is crucial for managing your email sender reputation and ensuring deliverability. Below is a list of ISPs and their FBL setup resources:

Major ISP Feedback Loops

1. AOL/Yahoo/Verizon:

   • Use Yahoo’s Complaint Feedback Loop (CFL) for Yahoo, AOL, and Verizon emails. Signup and resources are available at Yahoo Postmaster Tools: Yahoo CFL Application【12†source】【13†source】【14†source】.

2. Microsoft (Outlook/Hotmail):

   • Register at Microsoft's Sender Support to set up the FBL: Microsoft Feedback Loop【13†source】【14†source】.

3. Gmail:

   • Gmail does not offer traditional FBLs but provides aggregated spam statistics through its Postmaster Tools: Gmail Postmaster Tools【14†source】.

4. Comcast:

   • Apply for their feedback loop here: Comcast FBL【13†source】【14†source】.

5. Cox Communications:

   • Use their dedicated FBL portal: Cox FBL【13†source】【14†source】.

6. Rackspace:

   • Feedback loop details are available at: Rackspace FBL【13†source】.

7. Mail.ru:

   • Access their resources at Mail.ru Postmaster【13†source】【14†source】.

General Requirements for Setting Up FBLs

• Ensure your domain has SPF, DKIM, and DMARC records properly configured.
• Have a dedicated email address (e.g., abuse@yourdomain.com or postmaster@yourdomain.com) for handling complaints.
• Bulk email senders must meet specific volume thresholds, particularly for Gmail and Yahoo.