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I'm running bitcoin-qt 0.8.6 on a different computer that has the whole blockchain downloaded. I tried putting all the blk.dat files and the index from that computer the blocks folder in bitcoin-qt v.10 on a separate computer but it wouldn't load. I tried reindexing it but it still wouldn't load. I'm not sure if the chainstate is related to the process because I tried placing the original in the new bitcoin qt application support folder but it would cause it to crash before opening or everything would be erased upon opening.
I'm running OSX Mavericks on the original computer and Yosemite on the new one.