What should I do if my contact's ISP or spam filter is blocking Constant Contact mail?

How to work with ISPs who are blocking your emails

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What should I do if my contact's ISP or spam filter is blocking Constant Contact mail?

If you believe your email campaigns are being blocked by an ISP or mail server as opposed to being filtered, we suggest you start by reaching out to your subscribers (contacts) or their ISP (Internet Service Provider) directly.

If numerous subscribers from the same large domain (such as Gmail, Hotmail or Yahoo) or ISP (Comcast, Road Runner or Verizon) are appearing in the "Blocked?" bounce category in your account, please contact our telephone support team directly so we can take steps to resolve the issue.  Our ISP Relations Team has experience working with these large providers and will work to resolve the problem on your behalf.

For smaller ISPs and domains we have created the following letters to help you communicate with your subscribers and their ISPs.  Once the letters have been handed off, our ISP Relations Team will work with the appropriate individuals to resolve the issue.  The ISP Relations Team is available (via the ops@constantcontact.com address included in the letter) should the ISP/Domain require follow-up information such as mail logs.  We have found this approach usually yields much faster results since the admins are hearing from their own users who want the mail.

Important: When you copy and paste these letters into an email sent via your standard email and not through Constant Contact, please be sure to replace the XXX placeholder with more specific and appropriate information before sending it to either the contact or ISP.

Letter You Send to Your Subscriber

To: Contact
Subject: Contact Your ISP

Hello XXX,

I am emailing to alert you that your ISP is blocking the newsletters/promotions/announcements you have subscribed to receive. I know that you would like to receive these valuable communications, so I ask that you send the attached letter to your ISP's customer support department. Please be sure to replace in the XXXX areas below.

As you may know, Constant Contact powers the email communications I send. When you receive a response from your ISP, please forward the response email to the following address: ops@constantcontact.com. The Operations Department at Constant Contact will follow-up with your ISP once they receive your email.

I apologize for any inconvenience this may cause you.


Letter Your Subscriber Sends to their ISP

To: ISP Customer Support
Subject: Remove Constant Contact Block

Hello. My name is XXXX and I have been a customer of your services since XXXX. I understand that you employ filters and/or blacklists to protect customers like myself from unsolicited email; however, this has made it impossible for me to receive newsletters, announcements, and promotions that I have requested. I value these communications and would like to receive them using this email address.

The sender of these emails uses an email marketing service called Constant Contact. Constant Contact is not an open relay and has strict anti-spam policies in place. Because your filters block emails from Constant Contact I am unable to receive these communications.

I ask that you please help me determine why these emails are being blocked. For further information about Constant Contact or to request more information from them such as log files, the Operations team can be reached at - 781.472.8103 or ops@constantcontact.com.

Mail from Constant Contact can be found by the following characteristics for whitelisting:

"Envelope from:" domains:


Sending IPs:

All mail from Constant Contact is sent from:

IP Range: -

Specific IPs sending from this range:          coi001.confirmedcc.com          coi002.confirmedcc.com          coi003.confirmedcc.com          coi004.confirmedcc.com     coi103.confirmedcc.com     coi104.confirmedcc.com     ccm22.constantcontact.com     ccm23.constantcontact.com     ccm24.constantcontact.com     ccm25.constantcontact.com     ccm134.constantcontact.com     ccm135.constantcontact.com     ccm26.constantcontact.com     ccm27.constantcontact.com     ccm38.constantcontact.com     ccm39.constantcontact.com     ccm165.constantcontact.com     ccm166.constantcontact.com     ccm167.constantcontact.com     ccm168.constantcontact.com     ccm169.constantcontact.com     ccm170.constantcontact.com     ccm171.constantcontact.com     ccm172.constantcontact.com     ccm173.constantcontact.com     ccm174.constantcontact.com     ccm175.constantcontact.com     ccm176.constantcontact.com     ccm177.constantcontact.com     ccm178.constantcontact.com     ccm179.constantcontact.com     ccm180.constantcontact.com     ccm181.constantcontact.com     ccm182.constantcontact.com     ccm183.constantcontact.com     ccm184.constantcontact.com     ccm185.constantcontact.com     ccm186.constantcontact.com     ccm33.constantcontact.com     ccm34.constantcontact.com     ccm35.constantcontact.com     ccm36.constantcontact.com     ccm197.constantcontact.com     ccm198.constantcontact.com     ccm200.constantcontact.com     ccm201.constantcontact.com     ccm202.constantcontact.com     ccm29.constantcontact.com     ccm30.constantcontact.com     ccm31.constantcontact.com     ccm32.constantcontact.com     ccm229.constantcontact.com     ccm230.constantcontact.com     ccm231.constantcontact.com     ccm232.constantcontact.com     ccm233.constantcontact.com     ccm234.constantcontact.com     ccm235.constantcontact.com     ccm236.constantcontact.com     ccm37.constantcontact.com

Please contact me when this problem has been resolved.



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