Bounces and how are they classified

When an email message is not delivered to the intended recipient, it is an email bounce.

Three primary categories of bounces exist:

• Hard bounces: These are usually caused by incorrect email addresses or non-existent domains but are permanent delivery failures. Hard bounces mean that the email address will never get the message.

• Soft bounces: These are brief delivery failures frequently caused by problems like an overflowing inbox, server outages, or larger messages than allowed. If you resend the email, soft bounces might be fixed.

• Internal bounces: These can happen for multiple reasons, such as timed-out connections between servers or exceeded limits or spam filters blocking your email. They are usually temporary problems, and you can retry these addresses later. Learn about "internal bounces in bounce report".

Typical causes of bounces include:

• Misspelled email addresses

• Closed or outdated email accounts

• Problems with the recipient's server

• Spam filters are blocking the message

• Network issues