Will my Snow Leopard time machine files (going back several years) still be usable after updating to Mavericks? If necessary, would I be able to restore back to my current Snow Leopard HD? If not, do I just erase the (WD) external drive and start over? Thanks in advance for your help.
Mac mini (Early 2009), Mac OS X (10.6.8), 2GHz Intel; 4G ram; 500Gb hd + 500Gb ext hd