YippieMove:Email Data Backup Tool is an extremely simple mail transfer tool that can transfer mail from multiple mailboxes to a new mailbox, especially for replacement jobs, etc.

Yippiemove is not free. It costs $9.95 per account, but it's a great value because the backups include not only the contents of each email, but also the attachments in the email.

YippieMove has moved to developing APIs (Application Programming Interfaces) to provide enterprise customers with an API interface for mail transfer. As long as the enterprise mailbox is installed with the client software, users can easily transfer the mailbox contents by just logging in and clicking a few times.

Currently YippieMove supports more than 100 mainstream mailbox providers, and as long as the mailbox providers support IMAP (Interactive Mail Access Protocol), it can carry out perfect mail transfer.