All links in sent campaign showing “NET::ERR_CERT_COMMON_NAME_INVALID” from cc.rs6.net tracking domain

We sent a newsletter campaign yesterday (March 11 at 2:48 PM EDT) and are experiencing a serious issue with all links in the email.

Every link in the campaign redirects through a Constant Contact click-tracking domain similar to:

rdoplqfbb.cc.rs6.net

When recipients click the links they receive the following browser security warning:

NET::ERR_CERT_COMMON_NAME_INVALID
“This connection is not private.”

Because the error occurs on the cc.rs6.net redirect domain before the redirect reaches our website, it appears to be an SSL certificate mismatch or configuration issue on the Constant Contact click-tracking infrastructure.

We have confirmed this issue across:

  • multiple devices (Mac and Windows)

  • multiple browsers (Chrome, Safari, Firefox)

  • multiple networks and locations

  • several members of our team

As a result, recipients cannot safely access any links in the campaign.

We have already contacted support and they are escalating to a specialist, but I wanted to check if anyone else has recently experienced this issue with the cc.rs6.net tracking domain.

Has anyone seen this before or know if there are any current issues affecting Constant Contact link tracking?

Any insights would be appreciated.

Screenshot 2026-03-12.png
154.17KB

4 replies
Best reply by Kyle B

Hi folks,

This was an issue with an SSL certificate renewal on rs6.net, which is the domain we use for click and open tracking. At of 9:00am ET this morning, that change has been rolled back. Your links should now be working again, and your metrics will start flowing in normally.

Unfortunately, because of that issue, we weren't able to see and capture any metrics that were generated during that time. I'll update this post with the steps we're taking to make sure this doesn't happen again after we have our post-mortem this morning.

--Kyle

View original
Webinar

Join us to learn about successful email lists, from onboarding to database maintenance. May 28, 2026 - 2:00 pm ET

Popular Posts:

The world's largest virtual email marketing conference. November 12-13th.