Maybe you want to move to a different email provider. Maybe you need to export an archive for a new listserv. Either way, the best plan is to export your files from Gmail and Yahoo as a MBOX, an old Unix file type that’s still used for email archives across both PC and Mac. Here’s how to export a MBOX file from both these common email providers. Export a MBOX file from Gmail (Inbox) Gmail is the easiest of the two to export from.