When your IMAP mailbox becomes very large on our servers you may want to move all your messages to your computer to free up space.
In Mac Mail it is possible to create a Mailbox that is on the Mac only and messages from the IMAP server can be moved to this folder.
Here are the steps:
Create a local folder on the Mac
Follow these steps to create a local folder on the Mac:
- Go to the Mailbox menu.
- Choose New Mailbox.
- Set the Location for the new mailbox to On My Mac and enter a Name. Repeat this step if you want to create different mailboxes for Inbox, Sent Items, Important, etc.
- Select OK to create. The newly created Mailbox should be displayed under the heading On My Mac.
Move mail to the local folder to Archive
To move the messages from the IMAP server, all you need to do is drag and drop them from their respective folders to the new Mailboxes under On My Mac.
Messages can be moved individually or in bulk. In bulk, it is best to limit copy operations to a few 100 messages at a time. The operation can timeout and the application could become unresponsive if you try to move too many messages at once.
Compare the number of messages between folders before and after to ensure that it was moved correctly.