Will changing MX entry forward Inbox's contents?

How to get old server's e-mail on new server...?

I've switched cPanel hosters, and I've nearly completed the process of moving all my clients over.

I'd like to know if I can simply modify the MX records on my OLD hoster and have the e-mail that's already been received to the domain's Inboxes forwarded by doing this. Will it work this way, or will only new e-mail get forwarded, and the rest still have to be downloaded manually by temporarily changing the POP3 server on the e-mail client?

My new web hoster suggested copying the mail file/folder to the new cPanel account, but doing this would then erase current e-mail in favor of the old. I preferably need a way to MERGE the e-mail without having to switch between POP3 servers to get remaining, undownloaded e-mails.

Any suggestions? Thanks in advance for your help!

Matt

 

Well, I've found out that changing the MX entries doesn't forward the e-mail that's already been received, which makes sense. If I'm wrong about this, then please let me know.

I also found out that you can simply concatenate (as opposed to overwriting) the mail files! For example, I FTP'd into the old mail server & downloaded the mail files. I then FTP'd into the new mail server & downloaded those mail files to another location. After that, I opened the two files in a text editor capable of handling Unix text files easily, and copied the old mail file's contents into the beginning of the new one. Finally, I re-uploaded the new, combined inbox to the new server. Voila! Old and new e-mail on the new server ready for downloading.

This is rather lengthy, though. There's got to be a better way, right?

-- Matt