I have a running POP3 mail account. I have all mails already downloaded to my Mac with mail.app. I have left a copy of the mails on the server. I have backups of my main hard drive including my mail.app library. My mails are sorted into a folder structure within mail.app. What would be the best way, to switch this account from POP3 to IMAP? I want to be able, to receive/ organize/ answer/ delete mails on my computer or on the iPhone and sync these mails to either device. I realize, the iPhone does not support a folder structure similar to the desktop app. Therefore I want to have synced definitely: - mails to be deleted on the server, the iPhone and my desktop, when deleting them from either the Mac or the iPhone, - mails, I sent to any person to be synced into the "sent mail folder" of all sources. I can sort the mails into their appropriate folder on my computer and do not want this to interfere with the syncing of the 3 sources.