Error message: Updating the IMAP/SMTP endpoints is not permitted. Please contact Nylas support to do so.
Explanation: Just like this Exchange error message, this IMAP/SMTP error message happens because you've previously signed up for a service backed by the Nylas API while specifying a different server or port.
For security reasons, we require that all re-authorizations for an account use the same IMAP/SMTP server endpoints as the first successful authorization.
If you are certain you are using the correct IMAP/SMTP endpoints per your email administrator's instructions, please contact us so we may further assist you in correcting your server settings.