I wanted to back up the blockchain on my hard drive as it took around 50 GB on my laptop. I did so and deleted all the blk000.dat and the rev000.dat from (~/Library/Application Support/Bitcoin/) which are saved on my hard drive. Apparently this was a stupid mistake as I cannot open Bitcoin QT anymore. I therefore re-transfered everything back to the same folder. But nothing happens, and Bitcoin Core does not open.

After looking around, many are mentioning a bootstrap.dat file which correspond to the block chain. I cannot seem to find this file anywhere on my laptop.

Any clues? thanks a lot!


Delete your chainstate and blocks folder and start Bitcoin-Qt again. It will then re-sync your blockchain.


Forget about the bootstrap file. That's old and obsolete information.

Did you turn off bitcoin-qt every time before you copied or deleted files?

You may need to just let bitcoin-qt re-download the whole blockchain. Make sure you backup your wallet (wallet.dat).

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