When I upgraded to 0.8.1, it said Reindexing blocks on disk and it took about four days (Grr). But later, it said something about a corrupted database and it had to do it again! What is it doing?
0.8x versions of the bitcoin-qt client now use a different database to store the blockchain. This change was necessary to allow for larger block sizes.
The reindexing process is converting the previous database (which used BerkleyDB) into the new one (Which uses LevelDB).
The way the blockchain is stored on your computer has changed with the latest version.
The developers tweaked it, so that future users can profit from a faster init-proccess.
The new indexing made it necessary to reinitialize your blockchain.
However it should not have taken so long. On my laptop it took about 2 hours. Do you have a very weak computer?
protected by Community♦ Sep 15 '13 at 10:15
Thank you for your interest in this question.
Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).
Would you like to answer one of these unanswered questions instead?