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I access my three email accounts via my iMac (I have/use no other devices). I have set the IMAP port # to 993 and the SMTP port # to 465 for all three email accounts. I have the “automatically manage connection settings” checked for all three. I always download the most recent OS & security updates as they become available. Having laid all that out.... a frequent occurrence has developed since January 2018 - whereby my IMAP & SMTP port #s change on their own. This happens across all three of my email accounts - but not uniformly. Using this week’s latest example: only the IMAP port # on my primary email changed - and only the SMTP port # on a secondary email account changed - leaving my third email port #s totally fine. Even more curious to me is that many emails from my primary account were going through and were successfully received. However, this was not consistent - some folks never got any of my emails. Whenever I become aware of this issue, I now know to go into my Mail - Preferences - Accounts - Server settings to check the port #s. And I typically discover that - at a minimum - the Outgoing Mail Port # on my primary email acct has been changed from 465 - again NOT by me. How does this happen without my initiative - and how do I prevent it from happening again??!! Thank you in advance for any direction you can provide. My phone call conversation with Cox's Support rep this afternoon only got me confirmation that Port #s shouldn't change on their own - and that the best way to address my present concern was to enroll in Cox's $10/month expanded support program. After being a loyal Cox customer for 30+ years, I feel more deserving of a better solution.
I did have a very nice, detailed chat with Apple Support. Was informed that Apple does not have any way to impact my internet server provider's port # settings. So I seem to find myself in the most unfortunate position of being in the middle of two companies pointing fingers at one another. I don't see why I should be asked to enroll & pay for a "Complete Care" package when I'm just asking for a little guidance from Cox on how best to trouble shoot. While I appreciate getting a reply back from a Forum Moderator to confirm my posting has been read..... honestly, the response above only affirms that my "Complete" loyalty over these past 30+ years is insufficient to gaining access to the appropriate Cox Technical Support team member who could possibly shed a little light on how best to resolve this on-going problem.