IP blacklisted or Blocked by Google/Gmail
Bounce back email from google:
: host gmail-smtp-in.l.google.com[74.125.127.26] said:
550-5.7.1 [124.217.xxx.xxx 1] Our system has detected an unusual rate
of 550-5.7.1 unsolicited mail originating from your IP address. To protect
our 550-5.7.1 users from spam, mail sent from your IP address has been
blocked. 550-5.7.1 Please visit
http://www.google.com/mail/help/bulk_mail.html to review 550 5.7.1 our Bulk
Email Senders Guidelines. 4si26639409pbm.2 (in reply to end of DATA command)
Solutions
If you have any affiliates, please make sure they are adhering to our rules and that their IP addresses are not blacklisted or blocked by Google Gmail from classifying your message as spam. Delivery from your domain will get better over time if you and your affiliates are compliant. Please be aware that at this moment, we are unable to whitelist specific sites.
Method 1 – Being Added to Approved Senders List
You can ask your recipient to add your domain name to their allowed senders list in order to prevent email bounces brought on by restricted IP addresses.
Method 2 – Add Recipient Allow IP Address
The recipient’s IT administrator should add Gmail’s transmitting IP addresses to an allowlist in the event that the recipient’s mail server doesn’t support approved senders.
Mail Server
A device that sends and receives emails is known as a mail server. Consider a mail server as a mailman who ensures that mails reach their intended destination.
Domain
An IP address is given a name by the domain, which is more frequently known as a website or web address. A domain is something like Google.com.
SMTP
A set of industry-standard Internet protocols called SMTP (Simple Mail Transport Protocol) is used by two email providers (such as Gmail and Yahoo Mail) to transfer email messages to one another’s mail servers.
IP address
A digital device, such as your computer, is identified by a set of digits called an IP address (Internet Protocol address). They function similarly to your home address in that they enable data to get to the right Internet location.
POP
You may access your mail using a mail client like Outlook Express or Apple Mail thanks to POP (Post office protocol), which is a one-way download of your messages. Actions you take in the mail software (such marking a message as read) won’t be transferred to Gmail because it only supports one-way communication.
DNS
The web service that converts a website’s name to its Internet address is known as a DNS (Domain Name Server).