When scaling from a self-hosted setup to a managed solo business email, what are the critical troubleshooting steps for client login failures and domain configuration?

To resolve client login failures during migration, IT leads must sequentially check the network, full email username, password or client-specific password, sending/receiving servers, ports, SSL/TLS, SMTP authentication, and admin IP restrictions. For domain configuration, you must bind a customer-manageable domain to the enterprise email; if none exists, register one first. The service supports standard protocols (SMTP, IMAP, POP) using ports like 25/465, 143/993, and 110/995. However, actual server addresses and encryption methods are subject to the admin console or customer service. For persistent issues, provide the error logs and client version to the official support team.

Before configuring the domain, define the primary email address, such as a name, contact, sales, or service. Administrators must create accounts and set initial passwords, after which users must log in using their full email addresses. If login issues persist, provide the time of occurrence along with error details and client versions to customer service.