Module errors 

Structs

E_INVALID_MAILER_CONFIG

Mail configuration is incomplete or invalid.

E_MAIL_NOT_CONFIGURED

Raised when Mail::send() is called outside a request context without an explicit config.

E_MAIL_TRANSPORT_ERROR

Transport-level failure (SMTP unreachable, credentials rejected, …).

E_SEND_FAILED

The mailer accepted the message but sending ultimately failed.