Problems with receiving email from iCloud (Apple IMAP Server Problem)

Hi,

I use icloud for email since years on my Mac. Since two days I have trouble to receiving email, as I get the error

"Could not connect to this IMAP Server"

On the other hand sending emails via iCloud is no Problem. I dig deeper and tried the usual things on my Client site, but nothing helps.

The Connection Doctor tell me, that my Client connect to:

READ Aug 29 07:37:48.169 [kCFStreamSocketSecurityLevelTLSv1_2] -- host:p16-smtp.mail.me.com -- port:587 -- socket:0x600002068b40 -- thread:0x6000012696c0

235 2.7.0 Authentication successful

but this has no further Authentification attempt:

INITIATING CONNECTION Aug 29 07:37:45.876 host:p16-imap.mail.me.com -- port:993 -- socket:0x0 -- thread:0x60000142eb80

I test with telnet and can confirm, I get a response from the P16 SMTP Server, but the P16 IMAP Server simply close the connection.

I double checked - when I open a VPN (indepedend of in New Zealand, the US, Australia), etc I can receive emails from iCloud and everything is working.

When I end VPN, iCloud is working for around 5-10 Minutes (as the connection to IMAP persist for a while), but when the Drop this Connection and try to reconnect and authenticate, it is not working.

All this feels like an Application Firewall, that put my IP (Starlink) on the blocklist.

I talked to First and Second Level Support of Apple, their cannot help and has no way to escalate.

Any ideas (e.G. Force the Configuration to use another Server than p16 ?).

Frank