I would like to create a backup of a Gmail account into another Gmail account. There could be many reasons why would someone like to do this, but in my case my Gmail account got full but instead of deleting messages would like to archive them in another account.
I was thinking about using POP3 / all / fetch from another account, but I would like to keep the folder structure and POP3 destroys it.
As far as I know IMAP would be the best way to keep the folder structure, but when I tried it with Thunderbird, it could not reliable copy messages from one IMAP to another IMAP.
Are there any script or software (preferably running on Windows, but I can run Virtualbox), what would mirror an IMAP account to another one reliably?
Gmail itself can do that, as in associating an account with another and automatically grabbing the emails from one account to the other.
Go to ‘Mail Settings‘ –> ‘Accounts and Import‘ tab. You should see:
which does that exactly. You can choose whether to leave the emails on the other account or not. And I think that’s all you need.
The corresponding gmail help page
So, using a Google Apps account won’t do that. What you can do is backup your mails locally somewhere and upload/restore them to the new account later.
I think Gmail backup fits you. Please take a look at its features and notice its flaws(ie can’t handle labels that use characters other than [a-zA-Z0-9]) and also see this question related to having a Google Apps account.
Other than that, there is Gmail keeper that was made for Google Apps email users, as the site states. You may want to take a look at that.