[DUPLICATE] My external Thunderbolt drive doesn't seem to be recognized as a source for backup
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with Acronis True Image 2015. Only the main Macintosh HD drive is recognized as a source. I have two external WDC Thunderbolt drives. One for backup which is recognized by True Image as a destination. The other external drive has all of my source data and Acronis doesn't seem to recognize it, even if I try to set up a new backup project. It is formatted as Mac OS Extended and running under El Capitan.