Problem

When you send an email to a contact you receive a non-delivery report (NDR) with the following error:

Remote SMTP Server Returned: 553 mailbox example@example.com is restricted

Read more [[You receive non-delivery reports (NDR) when you send an email]].

Cause

There is a problem with your contact’s mail server.

Resolution

We are unable to resolve this issue as it is not part of the DomainsFoundry network.