You may have had problems sending email from South Korea.
If this is the first you have heard of your nation's email issue, I am very sorry to bring you unwelcome news. I hope you can accept my apology. I hope you can understand nobody says it's your fault. You just live in a nation with Internet companies that operate irresponsibly.
The two largest Internet Service Providers in South Korea, KORNET and Hanaro, let their customers send all the junk email they want. In the well-run parts of the Internet, that's considered irresponsible. It's very destructive and it costs everyone a lot of time and money.
These spam messages are usually relayed illegally through Micrsoft PCs with trojan infections, connected to consumer broadband services such as DSL or cable modem.
KORNET absoloutely refuses to talk to anyone about the flood of network abuse coming from their customers. Hanaro is just as irresponsible.
Since spammers are now able to use KORNET- and Hanaro-hosted servers freely, spammers have flocked to them. Any message from a KORNET network address is practically guaranteed to be spam, and any penis pill or mortgage lead spam is likely to refer to a Web server on Hanaro. Therefore it is no longer reasonable to expect responsibly-run networks to accept email from senders using KORNET or Hanaro.
Networks worldwide are blocking KORNET and Hanaro address space from SMTP contact.
If you are in Korea and you need to send mail outside of your country, get a Mail.com or Mailshell.com account. (I do not advise anyone use Hotmail or Yahoo. Those companies are not trustworthy.) If you're "technical", get a Freeshell.org account. You will need it to send reliably to the rest of the world. Your country will have poor email connections for years to come, even if KORNET and Hanaro start cleaning up today. You should complain to your government about your Internet provider's outrageous, arrogant, and foolish behavior.
If 1% of the 24 million businesses in the United States sent you a spam once a year, your email would be unusable. It would not matter at all if they had "opt-out" provisions.
To prevent the email system as we know it from being destroyed, responsible Internet access providers do not allow spamming. "Opt-out" is irrelevant.
If you had a legitimate reason to send email to a domain I serve, you can
If you find this policy inconvenient, your complaint is with with KORNET and Hanaro, not with the well-run parts of the Internet that don't want their customers' abuse.
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