I was recently asked to look at archiving old E-Mails from IMAP accounts so that the accounts could be deleted without losing the emails. Surprisingly, the options I found were limited:
- Use a Mail client such as Thunderbird. Configure the IMAP account you wish to archive, and then drag messages from each mailbox in turn to local folders.
- Purchase a commercial option such as BeyondInbox. Configure the IMAP account, and the program downloads E-Mails into folders for each mailbox, with subfolders for years and months. This is not configurable.
Whilst looking for Open Source alternatives, I came across this Python script from Rob Iwancz, which dumps E-Mails from a single folder in a GMail account to the local disk. I’ve now adapted this script to iterate through all the mailboxes in the IMAP account, and tested that it functions on non-GMail IMAP accounts. All that’s required is the username and IMAP server. The password is asked for when the script is run.