Hi,
Please be very careful when deleting subscribers who did not "open" an email.
The reason is that you can not check the receiver's mailbox to see if they opened your email or not. There are only two ways to you can know if an email has been opened.
The first way is when the receiver loads the images (and thus the tracking pixel) in the email from your server. But.... in most email clients the option to show images is disabled. Unless they click to show the images you will not see they opened their email. And even if do do load the images, some email platforms cache these iamges and you will still not be able to see the open. The second way is when a user clicks on a link in your email.
So if someone reads your email but doen't download the tracking pixel or doesn't click on a link they have read your email but you do not see it as an open.
So why care about open rate? The only reason to keep track of it is to check if changes in your campaign result in more or less opens.
If you have the Enterprise version you can see the opens in the advanced statistics of the campaign. And you can use it as a selection or filtering option in segments, mass actions and automations.
