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I made a transaction on March 13th, transferring .88 BTC from my desktop wallet to another account. I have a Mac and am using Bitcoin-Qt version v0.8.1-beta. The transaction did not go through, my wallet is "out of sync", and I do not have the .88 BTC in my wallet anymore. I have scoured the internet trying to solve this problem and have not found anything yet. Any help is MUCH appreciated!