カスタムアドレスへのメール送信失敗：「EHLO」後に接続が失われました

[supermathie (Michael Brown)]

@ToddZ

12246	86.228748	54.240.69.230	64.176.213.39	SMTP	103	C: EHLO a69-230.smtp-out.amazonses.com
12247	86.228791	64.176.213.39	54.240.69.230	TCP	66	25 → 50903 [ACK] Seq=19 Ack=38 Win=44032 Len=0 TSval=958362939 TSecr=1554444418
12248	86.228963	64.176.213.39	54.240.69.230	SMTP	220	S: 250-forum-mail-receiver.localdomain | PIPELINING | SIZE 10240000 | VRFY | ETRN | ENHANCEDSTATUSCODES | 8BITMIME | DSN | CHUNKING
12253	86.236796	54.240.69.230	64.176.213.39	TCP	66	50903 → 25 [FIN, ACK] Seq=38 Ack=173 Win=28032 Len=0 TSval=1554444426 TSecr=958362939

SES closes the connection in packet 12253 (FIN) for reasons known only to it.

As to why, this is something about which you’ll need to inquire to AWS.