Everytime I try to open my wallet this error comes up. I have shut the computer down a few times and removed the wallet and reloaded it a few times too and the error keeps happening.

Bitcoin - Error: Failed to connect to best block

If you can't see the picture, it is a error message which says "failed to connect to best block" and it makes the wallet not open.

  • i wish the editors were not so meddlesome...leave my questions alone please ...if you want to ask a question you ask it.... this is my question , Aug 6, 2017 at 23:20
  • Hello David, welcome to Bitcoin StackExchange. Users here are encouraged to improve questions, as all content belongs to the community. Your title was amended to be more descriptive and a few spelling mistakes were fixed. As far as I can tell, the core content of your question was not changed. If you feel differently, please feel free to edit your post to your liking.
    – Murch
    Aug 7, 2017 at 18:31
  • Please report this bug here: github.com/BitcoinUnlimited/BitcoinUnlimited/issues
    – MCCCS
    Aug 15, 2017 at 8:04

1 Answer 1


Your database is out of sync with your blockchain.

Restart with -reindex-chainstate to make it rebuild the database. This may take several hours or more, depending on the speed of your machine and storage.

  • Its taking REALLY LONG ..like going on two days...my connection seems to be pretty good:is there anything else 9 can do to speed it up...if i knew this would take SOOOO long i NEVER would have put anything in this crappy wallet.. can i do ANYTHING to get my crypto out of this crap wallet... I dont know why this PARTICUKAR wallet is so damn slow.. Aug 5, 2017 at 21:54
  • Every full node validates all of history, as it does not trust anything received from other peers. There are several ways to speed it up, in particular by increasing memory usage. There are several questions and answers on this site about that. Aug 5, 2017 at 21:59
  • No need to get embarassed or using capitals here. Noone here forced you to use this wallet. Pieter already answered the technical approach with more computing power and RAM. Also you could try to extract the priv key, and load it into a different wallet software. You may need to get in touch with BU devs. This may require deep knowledge, and certainly has a steep learning curve. As such it might be better to just resync for 2 days, especially if you are new to the environment. Aug 6, 2017 at 13:46
  • Yeah you could get your wallet.dat and upload it to a amazon aws bitcoind server. Would be quicker if you need it super urgently. Aug 7, 2017 at 19:20

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