SMTP 530 Email Error

SMTP Error 530 is an authentication error. Usually, this error indicates an unauthenticated email client. Other reasons for this error are blacklisting of sender IP or invalid email address. Refer the following to your IT team to check.

1. 1. Authenticate the email client
      The most common reason for SMTP error 530 is not authenticating the email client properly. This usually happens when the user is unaware of the setting of a new email client.
   2. Invalid Login credentials
      Similarly, invalid or incorrect login details result in this SMTP error.
      Some users enter invalid email address and email clients show error 530.
      Please double-check login credentials.
      Also make sure that the recipient’s email address is valid.
   3. Blacklisted Sender IP
      Another reason that can cause SMTP error is blacklisting of IP by recipient server.
      The sender IP address may have got blacklisted somehow. If the sender uses this server to send mails, then it shows error 530.
      In this case, please check if the recipient server has blocked the sender IP in order to request them to unban or whitelist it.
   4. ISP blocking port
      The default SMTP port is 2.
   5. If the customer’s ISP blocks access to this SMTP port, error 530 can occur.
      This is usually done as a measure to avoid spamming.
      A workaround we do is to configure SMTP to use alternate port and enable this port in the mail client settings to send mail via Outlook, Thunderbird etc.