Easily Transfer Archives of Old Messages From One Mac to Another
If you’ve used Messages for a while, you might not want your archived messages to go away when you upgrade to a new Mac. iCloud should back up and restore many of them, but if that story goes far enough, it won’t get it all. iMore will show you how to make sure it migrates to your new computer.
Basically, you just need the ~/Library/Messages folder ~/Library/Messages on your old computer, and then copy all the content from there to the same folder on your new computer. This will include archives and attachments. When you’re done, restart your Mac and your complete message history should be there. Go to iMore for a complete step-by-step guide.
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