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.... and you fail to mention the model SSD and firmware version... or how you installed or cloned the system
most people also move most of their user folder to another hard drive.
sounds like a more normal Mail + OS issue if just that.
hard restarts = directory corruption so don't reboot w/o first either Recovery Mode, then follow up with Safe Boot.
And maybe you have 3rd party hardware or software that is not compatible with 10.8.2 needs to be considered as well.
2008 model 3,1 also are having a lot of issues this year. Including another critical piece, what gpu it has.
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