If you believe your email campaigns are being blocked by an ISP (Internet Service Provider) or a domain, as opposed to being filtered, the way to handle the issue depends on the size of the ISP or domain:
When numerous subscribers from the same large email domain (like Gmail, Hotmail, Yahoo, etc.) or large ISP (like Comcast, Road Runner, Verizon, etc.) are appearing in the "Blocked" bounce category in your account, it may be because of a change in the ISP's DMARC policy.
Please contact us 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, start by reaching out to your affected contacts or their ISP directly. We’ve created two letters (below) to help you communicate with your contacts and their ISPs.
Once the letters have been sent to your affected contacts, our ISP Relations Team will work with the appropriate individuals to resolve the issue.
The ISP Relations Team is available (ops@constantcontact.com) should the ISP/Domain require follow-up information such as mail logs. We have found this approach usually yields much faster results because the admins are hearing from their own users who want the mail.
 | Important: Copy and paste both letters into an email addressed to your affected contacts, but don't send the email from your Constant Contact account. If your Constant Contact emails are being blocked, your affected contacts will never see the letters, so it's better to send them through your official business email. |
Be sure to replace the XXXXXX with the appropriate names when you send the letter to your contact. The XXXX in the letter is a direction for your contacts to replace the similar fields in the letter they send to their ISP or domain.
To: Contact Subject: Please Contact Your ISP Hello XXXXXX, 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 the information in all three of the XXXX areas in the attached letter. 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. Sincerely, XXXXXX
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 blocklists 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 safelisting: "Envelope from:" domains: @in.constantcontact.com @in.confirmedcc.com Sending IPs: All mail from Constant Contact is sent from: IP Range: 205.207.106.10 - 205.207.106.21, 208.75.123.0 - 208.75.123.255 CIDR: 208.75.123.0/24 Network/Netmask: 208.75.123.0 255.255.255.0 Specific IPs sending from this range: 208.75.123.2 coi002.confirmedcc.com 208.75.123.3 coi003.confirmedcc.com 208.75.123.4 coi004.confirmedcc.com 208.75.123.103 coi103.confirmedcc.com 208.75.123.104 coi104.confirmedcc.com 208.75.123.97 ccm97.constantcontact.com 208.75.123.98 ccm98.constantcontact.com 208.75.123.99 ccm99.constantcontact.com 208.75.123.100 ccm100.constantcontact.com 208.75.123.101 ccm101.constantcontact.com 208.75.123.102 ccm102.constantcontact.com 208.75.123.105 ccm105.constantcontact.com 208.75.123.106 ccm106.constantcontact.com 208.75.123.107 ccm107.constantcontact.com 208.75.123.108 ccm108.constantcontact.com 208.75.123.109 ccm109.constantcontact.com 208.75.123.110 ccm110.constantcontact.com 208.75.123.111 ccm111.constantcontact.com 208.75.123.112 ccm112.constantcontact.com 208.75.123.113 ccm113.constantcontact.com 208.75.123.114 ccm114.constantcontact.com 208.75.123.115 ccm115.constantcontact.com 208.75.123.130 ccm22.constantcontact.com 208.75.123.131 ccm23.constantcontact.com 208.75.123.132 ccm24.constantcontact.com 208.75.123.133 ccm25.constantcontact.com 208.75.123.134 ccm134.constantcontact.com 208.75.123.135 ccm135.constantcontact.com 208.75.123.136 ccm136.constantcontact.com 208.75.123.137 ccm137.constantcontact.com 208.75.123.138 ccm138.constantcontact.com 208.75.123.139 ccm139.constantcontact.com 208.75.123.140 ccm140.constantcontact.com 208.75.123.141 ccm141.constantcontact.com 208.75.123.142 ccm142.constantcontact.com 208.75.123.143 ccm143.constantcontact.com 208.75.123.144 ccm144.constantcontact.com 208.75.123.145 ccm145.constantcontact.com 208.75.123.146 ccm146.constantcontact.com 208.75.123.147 ccm147.constantcontact.com 208.75.123.148 ccm148.constantcontact.com 208.75.123.149 ccm149.constantcontact.com 208.75.123.150 ccm150.constantcontact.com 208.75.123.151 ccm151.constantcontact.com 208.75.123.152 ccm152.constantcontact.com 208.75.123.153 ccm153.constantcontact.com 208.75.123.154 ccm154.constantcontact.com 208.75.123.161 ccm26.constantcontact.com 208.75.123.162 ccm27.constantcontact.com 208.75.123.163 ccm38.constantcontact.com 208.75.123.164 ccm39.constantcontact.com 208.75.123.165 ccm165.constantcontact.com 208.75.123.166 ccm166.constantcontact.com 208.75.123.167 ccm167.constantcontact.com 208.75.123.168 ccm168.constantcontact.com 208.75.123.169 ccm169.constantcontact.com 208.75.123.170 ccm170.constantcontact.com 208.75.123.171 ccm171.constantcontact.com 208.75.123.172 ccm172.constantcontact.com 208.75.123.173 ccm173.constantcontact.com 208.75.123.174 ccm174.constantcontact.com 208.75.123.175 ccm175.constantcontact.com 208.75.123.176 ccm176.constantcontact.com 208.75.123.177 ccm177.constantcontact.com 208.75.123.178 ccm178.constantcontact.com 208.75.123.179 ccm179.constantcontact.com 208.75.123.180 ccm180.constantcontact.com 208.75.123.181 ccm181.constantcontact.com 208.75.123.182 ccm182.constantcontact.com 208.75.123.183 ccm183.constantcontact.com 208.75.123.184 ccm184.constantcontact.com 208.75.123.185 ccm185.constantcontact.com 208.75.123.186 ccm186.constantcontact.com 208.75.123.193 ccm33.constantcontact.com 208.75.123.194 ccm34.constantcontact.com 208.75.123.195 ccm35.constantcontact.com 208.75.123.196 ccm36.constantcontact.com 208.75.123.197 ccm197.constantcontact.com 208.75.123.198 ccm198.constantcontact.com 208.75.123.199 ccm199.constantcontact.com 208.75.123.200 ccm200.constantcontact.com 208.75.123.201 ccm201.constantcontact.com 208.75.123.202 ccm202.constantcontact.com 208.75.123.203 ccm203.constantcontact.com 208.75.123.204 ccm204.constantcontact.com 208.75.123.205 ccm205.constantcontact.com 208.75.123.206 ccm206.constantcontact.com 208.75.123.207 ccm207.constantcontact.com 208.75.123.208 ccm208.constantcontact.com 208.75.123.209 ccm209.constantcontact.com 208.75.123.210 ccm210.constantcontact.com 208.75.123.211 ccm211.constantcontact.com 208.75.123.212 ccm212.constantcontact.com 208.75.123.213 ccm213.constantcontact.com 208.75.123.225 ccm29.constantcontact.com 208.75.123.226 ccm30.constantcontact.com 208.75.123.227 ccm31.constantcontact.com 208.75.123.228 ccm32.constantcontact.com 208.75.123.229 ccm229.constantcontact.com 208.75.123.230 ccm230.constantcontact.com 208.75.123.231 ccm231.constantcontact.com 208.75.123.232 ccm232.constantcontact.com 208.75.123.233 ccm233.constantcontact.com 208.75.123.234 ccm234.constantcontact.com 208.75.123.235 ccm235.constantcontact.com 208.75.123.236 ccm236.constantcontact.com 208.75.123.237 ccm237.constantcontact.com 208.75.123.238 ccm238.constantcontact.com 208.75.123.239 ccm239.constantcontact.com 208.75.123.240 ccm240.constantcontact.com 208.75.123.241 ccm241.constantcontact.com 208.75.123.242 ccm242.constantcontact.com 208.75.123.243 ccm243.constantcontact.com 208.75.123.244 ccm244.constantcontact.com 208.75.123.246 ccm246.constantcontact.com 208.75.123.247 ccm247.constantcontact.com 208.75.123.248 ccm248.constantcontact.com 208.75.123.249 ccm249.constantcontact.com 208.75.123.250 ccm37.constantcontact.com 205.207.106.10 bbm10.send.creativ.email. 205.207.106.11 bbm11.send.creativ.email 205.207.106.12 bbm12.send.creativ.email 205.207.106.13 bbm13.send.creativ.email 205.207.106.14 bbm14.send.creativ.email 205.207.106.15 bbm15.send.creativ.email 205.207.106.16 bbm16.send.creativ.email 205.207.106.17 bbm17.send.creativ.email 205.207.106.18 bbm18.send.creativ.email 205.207.106.19 bbm19.send.creativ.email 205.207.106.20 bbm20.send.creativ.email 205.207.106.21 bbm21.send.creativ.email Please contact me when this problem has been resolved. Sincerely, XXXX
Copyright © 2025 · All Rights Reserved · Constant Contact · Privacy Center