Sorry for all the questions - I've spent hours trying to educate myself on this and maybe i'm almost there. The problem is I'm on restricted bandwidth. I started out with POP on all my accounts years ago, and that worked fine because then I had all my mail available offline. I wound up getting an IMAP account set up in addition to a POP account during an OSX upgrade, and Mail then re-downloaded every single email that was on the Gmail server. IMAP is acceptable, as long as it downloads the email so I have it offline. But I have trouble keeping the application from constantly connecting to the mail servers. I really only want it to send/receive mail when I ask it to, for example during free download hours in the middle of the night. POP seems better suited to my this satellite internet world which is more like the old dial-up world than the modern rich access that all you city people can get.
I have a copy of Postbox 4 that I got in a MacHeist bundle, and I don't mind the interface. I installed it in offline only mode and fooled around with it to see if I could migrate all my existing mail and run the two applications alternating for a while to see which one I liked better. But Postbox doesn't have the documentation that I need, and they don't have a user forum, so I haven't been able to figure out how to import my existing accounts and folders. It did a good job, I think, of doing something but I can't figure out what. For example, I can't tell if Postbox is using the same folders as Mail, or if it made its own copy. And I can't figure out how to import my multiple inboxes from Mail into Postbox.
So if I had to use IMAP - which if I can force it to be quiet would be OK - I have another problem. I have multiple email accounts, and a large assortment of folders. I shove emails from various accounts into the folders, in addition to leaving some in the individual inboxes. I've deleted many messages and moved some to folders. This seems to confuse IMAP. I've already run into the situation where the email account re-downloads all the moved/deleted messages when I moved from my old G4 PowerBook to the Intel OS. Really would like to avoid doing that again and using up all my bandwidth allotment, not to mention the time to sort out all the duplicated messages.
I would like to migrate a group of email accounts, with multiple inboxes and multiple sub-folders on my mac, into another email client in such a way that I don't trigger a redownload of all the files that were moved from the inbox into folders. Gmail doesn't do folders, it just has the one inbox. If there is no way to do that, how about moving maybe I can import one account at a time and allow the new mail program to redownload/synch everything during "free zone" time. After that, I'll have a bunch of messages re-downloaded into my inbox that I have already moved into folders. I'm guessing they will be marked "unread" and I can just delete them. Then I will be left with the messages that were already in the inbox. But it seems that this could cause problems.
1. If I delete all that newly downloaded mail, won't the server then delete the corresponding messages from my online inbox? I like keeping them on the server just in case, even though I do backups.
2. Is it correct that the messages already moved into subfolders will remain, even if the original is deleted from the server?
3. Is there a way to import my existing inbox into another client in such a way that the server recognize those messages, or will it be confused by the fact that I'm using a different client and redownload them again anyway?
4. Mail is driving me crazy because it will work for a while, then all of a sudden one of the accounts will no longer be able to send mail. I can't edit the account because Mail won't allow me to have the same SMTP server name for two different accounts. For some reason I have for some accounts both an IMAP and a POP account, and then there is also something called an Internet account with the @ sign. Making a change to an existing account sometimes creates a new one, and then I can't delete it because there is an Internet account with the same name ... I CANNOT figure out how to clean up the Mail accounts so I have just the ones I need. I guess Apple is trying to force everyone into the connected world where I the computer and phone and tablet all live together, and maybe that's OK if you have bandwidth out the wazoo, but I don't. Is there some way to fix Mail so that the duplicate accounts are gone, or will Apple just break it again?
5. Lastly, does Airmail work better in this situation than Postbox? Multiple accounts, subfolders?
This little forum is my lifeline, thank you ...