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Once you've removed all the large emails, you can then view your emails by subject and, for example, if you get marketing emails from Amazon or Ebay, you can sort by subject and delete all of these emails at once if they use the same subject pattern.
Archiving Emails Locally
Apple Mail on Macs
In the left column in Apple Mail is a section called "On My Mac". Any email folders and emails copied and pasted or dragged into this section is stored locally on the machine. Users can copy and paste emails from their Exchange inboxes into the folders in "On My Mac" to create a local archive of the emails. Keep in mind, however, that any emails you put here will ONLY be available in this particular local machine. This may not work if you require your archives to be available on all the machines you use.
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