To avoid having to redownload everything from the p2p network, which may be slow as you have to validate the whole chain, you can download the bootstrap chain file from bitcoincharts.com
It is also available through bittorrent, which may be faster for you. Here's a copy of the message posted above and in the forums that authenticate the file (through GPG).
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Torrent info hash: 0bb0521942f586ed96203c6f4d136324756f8a9a
Torrent magnet link:
magnet:?xt=urn:btih:0bb0521942f586ed96203c6f4d136324756f8a9a&dn=bootstrap.dat
Filename: bootstrap.dat
Byte size: 2491771562
SHA1: e70ca90775dfdb13fd0014425805a0bdf4a31677
SHA256: a3f258e7af030165360596e4cb0b9beb24b4ce97352c22e65349b89ad5fc5d3e
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)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=uwRB
-----END PGP SIGNATURE-----
Also, here's a magnet link that includes trackers:
magnet:?xt=urn:btih:0bb0521942f586ed96203c6f4d136324756f8a9a&dn=bootstrap.dat&tr=udp://tracker.openbittorrent.com:80&tr=udp://tracker.publicbt.com:80&tr=udp://tracker.ccc.de:80&tr=udp://tracker.istole.it:80
Finally, as explained in this answer, you can also simply discard the index and regenerate it using the existing ondisk blk000?.dat
files, using -loadblock=blk0001.dat
and by deleting blkindex.dat
.
Edit: note that with bitcoind 0.8 and up, it's actually easier and faster to just download the block chain from the network directly, so don't bother with the bittorrent/manual download.