How To Read Email Bounces As Attachments

This is what an email bounce as an attachment will generally look like.
I will highlight the important bits with a red box for you.

This will be the email address that rejected the message. Always.

There are usually two or more attachments.
The first one is the only one you will need to worry about.

This is what you will see after opening the attachment.
Again I will highlight the important bits with a red box for you.

This is the area that you need to look at to find the necessary information.
You can generally ignore everything else in the message.

This will be the email address that rejected the message. Always.

This is the reason that the message was rejected,
and is almost always pretty direct in the reason why.
In this case the address is being rejected by the recipient server.
Which usually indicates an invalid email address.