Emails were based on the Simple Mail Transfer Protocol (SMTP) to send and receive e-mails between users. These days two more protocols, namely – IMAP (Internet Message Access Protocol) and POP 3 (Post Office Protocol), are also used for retrieving emails. Once the email is composed and the send button is clicked, it is forwarded to the Mail Transfer Agent (MTA) using the SMTP.
SMTP resolves the IP address of the mail server of the domain name with the help of the Mail eXchanger (MX) records. Once the mail server is located, SMTP transfers the email to the destination server, where the user can retrieve it using IMAP or POP3.
The most common issue with an email can be not being able to send or receive emails. First of all, make sure your internet connection is working you can reach your mail server, and that your mailbox is not full. You should also keep in mind that the maximum size of an email has not been reached and the maximum number of recipients that can be added to an email has not been exceeded. Also make sure there is no email, which was failed to be delivered in your outbox, either delete that mail or move that to the drafts. While accessing your email, you should remember that the email address and the password are case sensitive, so make sure you are entering the correct credentials. If you can send an email but cannot receive then check the MX records of your mail server domain. And in case you can receive but cannot send an email then make sure that port 25 (SMTP) and port 587 (Authorised Submission) are not blocked on your network. In case you are receiving bounce back emails regarding the non-delivery of the email, then try to look for the reason within the bounce back email.
Generally, these emails contain the reason for the bounce back. The most common reason for a bounce-back is that you’ve entered the wrong email address of the recipient. Another reason can also be that a part of your email has been sensed as spam and in turn not sent to the intended recipient. About 75% of the email traffic worldwide is spam. Make sure you deploy enough protection measures to save yourself from the vulnerabilities of a spam email. Be very careful while setting up a new firewall or anti-virus software as they can sometimes disable your mailing settings.
Finally, if you can not understand the error code generated by the email, try to look up the code over the internet search engines.
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