Switching a mail provider is often combined with one major thought holding one back: What will happen to all my e-mails? I don't want to lose my e-mails!

Sure, if you used POP3 to download the e-mails to your mail client, the e-mails are not stored on the server anymore. This worked fine in the 90s and 00s but since mobile Internet there are usually multiple devices connected to your mailbox: Notebook, Workstation, Smartphone or even a Tablet. In such a scenario, only IMAP (IMAPv4 to be precise) can do the job: All the e-mails remain on the server (in the mailbox) but are synced to the local mail client. Every change in the local mail client is synced back to the server. Hence all the devices see the same status.

For a customer of Infiniroot we recently needed to find a way to migrate all the existing e-mails (more than 28'000) from a long-existing mailbox to a new mailbox located on the dedicated server of this customer. This is where we came across imapsync.