It's because they positioned a throttle or Restrict on their IPs to mail specific emails, say for each hour or each day. This particular feature built them a no-Opt for spammers. Legitimate businesses will probably be content sending say 5k emails for every hour. A spammer will normally would https://ftpserverinstall00009.blogofoto.com/57652022/5-tips-about-nginx-ssl-certificate-install-you-can-use-today