I get an error message in Apple Mail for my iCloud account on iMac

Have spent 2 sessions of 1 hours each time with Apple Support

They acknowledged there was an iCloud Mail Servers issue last Friday to this Monday

It has since cleared up on the 3 M2 / M1 plus iPhone 14 all running the lAtest and Greatest Offering from Apple

I did find a Temp Solution and yes the issue is embarrassing. 

System Setting >> User ID  >> iCloud >> iCloud Mail >> Sync this Mac and switch OFF and Pause

Reverse the last step to ON in iCloud mail then,  Mail Application functions as Designed and Intended 

The above needs to done with Mail Closed Completely and then reopened

Apple - Support - System Status

Once in a while I get this issue but generally taking the Account Off Line and pause

Then, reverse to previous step will resolve this issue

Tested on 1 M1, 2 M2 and 1 M3 all running Sonoma 14.4

RN12 wrote:

On my iMac, I get an error message in Apple Mail for my iCloud account, with a warning triangle beside the account name inbox. Clicking on the triangle gives the message: "Connections to the server “p39-imap.mail.me.com” on the default ports timed out."

I have not seen any messages on this. Does anyone have any ideas on this? It does not happen on my Air.

Thanks.

see if there is anything here—

Mail on MacBook pro (high sierra) not wor… - Apple Community

iCloud Mail server settings for other email client apps

I see no wide spread issue on the server—

Apple - Support - System Status

I have this happening on my new Mac mini - 2 weeks old. There isn't an issue with our MacBook and we have not touched our settings.