Assistance with IMAP accounts

This question came up at another forum, but I don't know the proper answer.
An individual felt very strongly that he needed to back up his IMAP mail. From what I can see IMAP mail, set up in NS or Thunderbird has only the .msf files.
And, in my experience, it appears that IMAP accounts like the old @netscape.net, and present @aim.com kept their mail on server, so there should be no need for backups. Unless, of course, there have been some changes in the account, like change of password. What I don't comprehend is that there could be two inbox.msf files, one in the backup folder, with the old mail, and another one, identically named in the present folder. Or, would one find two folders, even in a current mail, like the ones found with pop mail? Can one retrieve the old inbox.msf, may be by renaming the file, or are backups, effectively, useless.
The entire concept slips away, and any help is appreciated, although I think that I have a partial answer, having two aim.com accounts, and four imap.aim.com folders. Two of them created in 2005, when I first signed up with AIM, and two created in late Aug.2006, when the netscape.net mail was discontinued. I see the headers, but that's it.

 

I agree with you Westside.
The strength of IMAP accounts is two fold based on one centrally located file set, which is NOT stored on the local user computer. The local user has no email files on his computer to backup. The local computer displays the remote files and with suitable IMAP software can view / write / delete information contained in the file set. Also the same user / multiple users can access this files set (simultaneously, with proper credentials, configuration) from any computer in the world. This provides ONE file set which is always "real-time current" managed from one / multiple computers. The one short coming ... you rely on someone else to provide "proper backups / access / availability" to this file set. The local user can protect himself if files are important / vital. Set up a local POP account on their computer and FROM IMAP view, select email records and COPY TO local POP account (Inbox and Sent). A potential automatic systems could be created. If IMAP server / ISP email server provides a "send copy of all emails to additional email addresses." this would catch all INBOX traffic. The "Sent" email becomes more difficult. Most email clients include "place copy of Sent emails" to a location which could be in a different email account. But gets muddy per ONE copy TO and/or copy to IMAP and other email account(s). Additionally the same problem if user creates "Sent" from multiply computers. For the "Sent" file a manual "COPY TO" from the IMAP account to your local POP account would be the simplest.

 

Dennis,
I did not even think of the Copy, but it happens that I have done it for years. I have a Misc. folder where I paste IMAP mail, as well as forwarding mail from Webmails. One example is Yahoo, which could be set up as a POP account using freePOPs, but I have been unable to have it accept my password since Yahoo Beta. So, I forward those e-mails to a POP account, and move them to a folder.