I am finally backing up Gmail. 6 years. 45K messages.

I am using a local backup. It is about time.

1. Download a secondary mail program - I am using Mozilla Thunderbird.

2. Put the mail files on an external drive (that takes a tiny bit of doing)

3. Create a POP connection to the gmail account and just download files for, like, ever.

I'll let you know how it goes.