It may seem odd that you can't just delete someone from a mailing list, but there are good reasons why eNotify was designed so that recipients must be unsubscribed and not just deleted.
Unsubscribe information is preserved within the module so that the user is not returned to a mailing list they unsubscribed from. If you send someone an unwanted email, even accidentally, and that person complains to their ISP, you may be blacklisted and your mass emails will not be delivered to anyone else who uses that ISP for a long time.
For example, let's say firstname.lastname@example.org unsubscribes from your list, and you delete him from the list. Later, you're uploading new names from an outside database or spreadsheet and you accidentally upload email@example.com into the list again. If you'd kept the existing "unsubscribed" status, that email address wouldn't be added to the list. Since you erased that status, though, Bob is going to get an unwanted email. At best, he's going to be irritated at you. At worst, he might report you to his ISP as a spammer.
Keeping the list of unsubscribed addresses within eNotify enables the module to perform a cross-check at the time of adding new email addresses to the list and helps prevent such mistakes and protect your sender reputation.
Resubscribe recipients who mark email as spam
If a user isn't receiving emails, it may be because they've marked an eNotice as spam, and it's possible for you to add them back to the list.
The email software that sends messages from eNotify automatically tracks the feedback provided by users. If a user clicks the "report this message as spam" button in their email client, eNotify will assume that user no longer wants to receive any email and will unsubscribe that user's email address.
Some users will select this button inadvertently, or will want to only identify one particular kind of communication as unwanted. In this case, you can clear the "spam" setting for that user and restore email deliveries.
To remove a user from the "Global Unsubscribes" list, go to eNotify > Mailing Lists > Global Unsubscribes. Find the user, select the checkbox next to their entry, and click on "Resubscribe Selected."
After resubscribing someone from the unsubscribe list, it's a best practice for somebody from the school to contact the user and explain what happened so that the situation isn't repeated. It's not a good idea to resubscribe someone without their knowledge, as it increases the likelihood that person will report you to their ISP.
This process helps to protect the sender reputation of your domain and our IP addresses, making sure that the messages you send are delivered to your end users.