I have a weird problem that started just today. I am using Apple Mail on a Leopard machine, connecting to Gmail. Fetching e-mail works just fine. My SMTP settings are also correct. Still, I can't send mail, it will display a pop up saying that "transferring the content to the mail server" failed (translation from German, could be different in English OS X versions).
I have verified the following:
- My SMTP settings are definitely correct. I have not changed them and the issue appeared today.
- Also, I went through the Apple online configuration for Gmail accounts and did not have to adjust any setting.
- I can run network diagnosis and it will connect to both POP and SMTP servers without a problem (all green lights)
- The Telnet details will show me the HELO message from the Gmail servers, so there's no authentication failure.
- Console.app will not show any messages related to "mail" when I try to send the mail, so there's no specific error message
- The mail I'm trying to send does not have an attachment, it is plaintext only
- I can login to gmail.com and send mails without a problem
- The recipient address exists and contains no syntax errors
- I can also not send mails to myself
- When using another IP and ISP (through VPN), it still doesn't work
As for my settings: I connect to smtp.gmail.com and for advanced settings I choose password-based authentication with user: [email protected] and my password. I let Apple Mail try the default ports (for SSL and TLS, respectively).
Again: I have not changed a thing between yesterday and today.
What What is causing that strange behavior? Any help would be much appreciated.
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