Hi everyone,
I have been using a OTENET (Cosmote, Greece) e-mail account (apel50@otenet.gr) in Thunderbird on a laptop for years. But since a couple of weeks I have a pro… (ketahui selanjutnya)
Hi everyone,
I have been using a OTENET (Cosmote, Greece) e-mail account (apel50@otenet.gr) in Thunderbird on a laptop for years. But since a couple of weeks I have a problem with outgoing mail. No changes in configuration.
=> Incoming mail: Works still perfectly via POP3 (mail.otenet.gr, port 995, SSL/TLS).
=> Outgoing mail: Consistently fails on mailgate.otenet.gr. Tested on port 465 with SSL/TLS and port 587 with STARTTLS, as well as via different network connections/hotspots, and just to be sure also on smtp.otenet.gr. The following error:
"Verzenden van het bericht is mislukt. Er is een fout opgetreden bij het verzenden van e-mail. De mailserver antwoordde: Reject, id=18742-18 - SPAM. Controleer het bericht en probeer het opnieuw."
I have already contacted Cosmote support, and they verified that the account status is completely fine and that smtp.otenet.gr is indeed the correct and active outgoing server. Even a simple, plain-text test email with a normal sentence gets rejected immediately by their server-side filter (amavisd / SpamAssassin).
Could this be related to a specific header, authentication method, or sender-identity mismatch in Thunderbird when communicating with modern Telekom/Cosmote SMTP infrastructure? Any advice on what to check would be greatly appreciated!
Warm regards, Anna