I'm experimenting with sending a large email mailing using
Java's email API to permit me to attach files and insert images.
The problem I'm addressing is ERROR 452. I.e. Domains like Yahoo that will not permit too many emails from a single sender to be delivered to Yahoo email accounts in too short a time period.
For example, sending to a list with say 25 "@yahoo.com" addresses will trigger its SPAM blocker. It will not deliver the message. Instead it will return ERROR 452 message to the sender.
When I want to use the list for TO: addresses it's easy to overcome that problem, because I can code a delay between each send that is sufficiently long to avoid triggering ERROR 452 by the domain that has such a blocker.
When I send an email to a single TO: address and put my long list as BCC: addresses I can't figure out if, or how, I can spread out transmission of the BCC: copies.
So I need to learn more about how Java API works.
More specifically ... assume I create a message with a
-- single TO: address and
-- 50 BCC: addressees.
1. Does the App send a single message to the ISP server that relies on the ISP server create a separate message for each TO:, CC:, and BCC: addressee? (Bad ... because then I can't delay transmission of BCC: messages to dodge the 452.)
or
2. Does the Java API create the separate messages required for each addressee and send them to the ISP for delivery? (Good ... In which case it seems I have a hope of transmitting the copy for each BCC: addressee at delayed intervals)
or
Does anyone have any other suggestions for how to deal with long BCC: address lists?
Thanks,
glb