Here are instructions for enabling open-rate tracking in your CCtoMany list:

Include this image in your HTML, usually at the bottom. You can include this image in your template file so all new messages have it automatically.

<img src="">

When properly included, the image will look like this (you will probably want to center it):

As each recipient's message is built, that link gets converted to a unique encoded URL which is then used to track each individual open event. So DO NOT copy the tracking image link from a message you've received! That image is linked to ONLY your own email address.