Hi @felixlamour,
Thanks for giving us some more information on the issue.
When emails are sent from the plugin’s end, they get marked in grey check mark and after they get opened, they are marked as opened with a double green check mark.
Below are few cases when an email isn’t marked as opened
1) Email open tracking isn’t enabled in the campaign
If open tracking isn’t enabled then there status doen’s change when someone opens them. Can you please check if open tracking is enabled in the campaigns?
2) Emails are getting delivered into the spam folder
When emails get delivered into the spam folder, they aren’t tracked. There are many factors which cause an email to be delivered into the spam folder. You can read more about them from here.
3) Subscribers have disbled images in their email client
To track opens, the plugin embed a tiny invisible image into the email. When images are disabled in the email, this image doesn’t get rendered and thus email opening can’t be tracked in this case.
On the reports page, are all emails are with grey check mark? If some of them have grey check mark, then it is possible that email got delivered into the spam folder. If all the emails have this issue, then the issue might be with the sending process. We might need to debug it further to understand the issue. You can contact us here if you want us to look into this issue further.
Hope this helps you. Let us know if you have any further queries.
Thank you.