When you are using AppleMail, or some other mail client, you may experience issues where your IP address is becoming blocked due to attempts to access port 585 on our server(s).
Some mail clients incorrectly try and use port 585 for secure IMAP communications (dubbed IMAP4-SSL), however most hosting providers utilize IMAP4 over SSL (dubbed IMAPS) which instead uses port 993.
Attempts to access port 585 can result in your IP address becoming blocked because of the security systems they have in place that look for connection attempts to invalid ports, and block the offending IP address when it may be considered a port scan.
This could lead to your whole account being blocked and all your mailboxes and websites within that account will be blocked and stop working.
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