I have encountered a new problem. A few of my users have signed up with my site using their Apple ID. While I am not certain, I believe that this option is only made available to users who are using the iPhone version of my CSNet app.
The problem is that this creates really weird user email addresses. But more importantly, when I attempt to email these users by clicking on their Apple ID email address on the Members page in the AdminCP, Apple's mail server is rejecting my sent email and is not delivering it to the user, with the error message that it will not accept relayed mail. Here is an example:
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Message not delivered
Your message couldn't be delivered to zycxbr4jjh@privaterelay.appleid.com because the remote server is misconfigured. See technical details below for more information.
The response from the remote server was:
550 5.1.1 Relay not allowed
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So, I would like to disable allowing my new users -- or any user for that matter -- from being able to use their Apple ID email address. How do I do this? Is there a setting somewhere in the AdminCP, or is this something that is built into the CSNet app itself?