Email Sent Successfully But Not Received
You sent an email using Nylas and received a 200 response from the API, but the recipient never receives the email.
This is usually due to one of the following issues.
Sender's Server
The user’s email server received our request to send the email and returned a successful response to us, but failed to send on their end.
For all /send API requests, Nylas does not send the email. Instead we hand off the request to the user's email server.
If you notice the user's sent emails to multiple recipients are failing with no bounced email messages, the user should reach out their email administrator to learn why the messages failed.
Bounced Emails
Check to see if there was a bounced email from the sender or recipient's email server in the sender's Inbox.
The content of the bounce emails usually describe the reason for the send failure. In most cases, the email administrator needs to be contacted to resolve the issue.
Email Was Blocked By the Recipient’s Server
The email may have been flagged as spam on the recipient’s end. You can check the Junk folder or see if they have a filter that prevents the email from reaching their Inbox.
Learn more about Dealing with Spam.