Hello Angela,
Your question intrigued me, so I did a little poking online. (I use Gmail for my personal, not business, email but creating an email archive outside of Google is probably wise step for me anyway!) I found a
link to an article explaining the uses of Google Takeout that may help, but it would still require getting access to the old email account in question. If this method for saving email is used proactively by your current staff and the resulting files are saved in shared location, you shouldn't need access to accounts after staff leave in the future. The official Google Takeout page is
here, and you can click in the different categories of data to learn more about how they are stored.
When you create an mbox file, there are various converters out there that will allow you to convert it into a PDF if you want, or you can open the file in gmail or another email client.
Here at the Met, we are still doing things the old-fashioned way-- printing the important emails where decisions are made and adding them to the permanent paper files for our Archives-- even as we explore ways to save electronic data. I still think paper is a good back-up for the really important stuff until you have a robust plan in place for keeping up with your digital files, and until there is more consensus about file formats and storage solutions for the long term. (I'm not an expert mind you, but this is what I've gleaned.)
Good luck!
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Romy Vreeland
Manager, Board of Trustees and General Counsel's Office
The Metropolitan Museum of Art
New York NY
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