When sending email via SendGrid, you may encounter the following error:
SMTP error from remote mail server after end of data: 550 The from address does not match a verified Sender Identity.
This issue occurs when the sender of the email has not been verified via SendGrid. More information regarding the error can be found here:
The preferable solution would be to verify the domain of the sender via Domain Authentication
This would be preferred over Single Sender Verification because you cannot verify system email addresses such as root@hostname without Domain Authentication since they cannot receive email.