31

this is a generic answer applying to "light" wallets - I don't know much about the blockchain.info-wallet There are several approaches that may work. I'm not sure which methods are most easily available for a user of a blockchain.info-wallet, but probably #0a and #2, followed by #3, #0b and #1b. 0) Wait it out. 0a) Wait for the transaction to go through. ...


22

Answer shamelessly stolen from stackexchange: Difficulty encoding is thoroughly described here. Hexadecimal representation like 0x182815ee consists of two parts: 0x18 -- number of bytes in a target 0x2815ee -- target prefix This means that valid hash should be less than 0x2815ee000000000000000000000000000000000000000000 (it is ...


21

Blockchain.info pairing code allows you to sync wallets. For example, it's for when you have coins on your phone and you want to be able to spend them from your computer. So, they synced their wallet with your account, including the private keys, and stole your coins. From their website: As with your wallet ID, you should never share your pairing code ...


12

Cancelling unconfirmed transactions is easy. Just submit a higher fee double-spend transaction. For example: if you send a 0-fee transaction it could take a day before 1 block mines it. Then you send another transaction with the same inputs that just sends the money back to yourself. On this transaction you put a higher fee. This becomes more ...


12

It seems obvious to me that this is a scam. No legitimate investment in the world can guarantee a rate of return of 20 percent per day. At that rate, with a 5 btc initial investment, you'd own all the bitcoins in existence after 81 days. And after 15 months, you'd have this much. But you may want to contact blockchain.info directly; there is a contact link ...


11

Messages are stored in a database at blockchain.info (so that text should probably be changed). For a while it did use the blockchain for storing messages but this was changed after concerns from a few of the core developers. Concerns were expressed by Matt Corallo here Oh god, thats awful...that is quite possibly the worst way to implement messages in ...


11

To download the blockchain with maximal speed you want to be connected to nodes with high bandwidth. On default bitcoin will search and connect to random nodes. One can add nodes to bitcoin conf to tell bitcoin to connect to specific nodes. To add a node to the bitcoin client to connect to, add the following to the bitcoin.conf file in: Windows:/appdata/...


10

Look at a list of Litecoin web wallets to see if any one them sound familiar to you: LiteVault - Online Litecoin Wallet; private keys encrypted locally Hive Web Wallet - Online BTC/LTC wallet; private keys encrypted locally Liteaddress.org - Litecoin address generation tools (BIP38) Reddit LiteTip Bot - Give and receive Litecoin tips from reddit users ...


9

I can't elaborate much on your answer but can provide reasons as to why this market seems so bare. Apple has shut down other providers of BitCoin wallets for "legal reasons" -- all due to the legal ambiguity of BTC transactions. Your best bet is to look into mobile-optimized websites that offer BTC transactions. I'm unfortunately not too knowledgable on ...


9

Obviously, he is a scammer trying hard to look similar as the Blockchain's Official Investment scheme but there isn't anything like this ever before. Many scammers are there, one of the most luring advert is 'Earn through Bitcoin Mining from Antminer(S9)'. In the name of Antminer(S9) many persons reaching out through various social platforms to you and ...


9

You can't include the USD amount, but you certainly can include the btc amount in the QR code. The QR code essentially embeds a text like this: bitcoin:1ArmoryXcfq7TnCSuZa9fQjRYwJ4bkRKfv?amount=0.005 Note the amount here is the amount in BTC. You can generate a QR code for that text using gobitcoin.io. If you just want to insert an image, you can use ...


9

However this is JSON, I imagine I can't use it to verify the nonce. You can. You can build the block header using the data at the beginning of the JSON object and then hash that. Of course it would be easier to get the block hex, which you can get by going to the block hash on blockchain.info and appending ?format=hex to the url. For example, for the block ...


9

If you look at the output script for that output, you can see it looks like this: RETURN PUSHDATA(32) [some garbage] This script, beginning with OP_RETURN, is called a null-data output, and is used to store arbitrary data in the blockchain. These outputs can never be spent, there is no way to make the script ever evaluate to true. Because of this, they ...


8

Public notes are simply attached to addresses/transactions in the blockchain.info database, not in the blockchain itself, it's more of a convenience service offered by this particular website than a protocol feature. And yes, you can make them on blockchain.info, you apparently do not need to own an address to tag it (some of my addresses got tagged without ...


8

You cannot. That feature has been was "temporarily" cancelled due to numerous reports of stuck transactions and growing awareness of its privacy limitations: https://blog.blockchain.com/2014/03/17/shared-coin-suspended-temporarily/ http://www.coindesk.com/blockchains-sharedcoin-users-can-identified-says-security-expert/ I dont think the previous version ...


7

Okay, so after investigating the provided restore tool (thanks Lohoris for pointing it out!), I arrived at the following answers to my questions: The input key for the AES decryption is 32 bytes (256 bits) The block size used is 16 bytes (MCRYPT_RIJNDAEL_128 for PHP mcrypt functions) The initialization vector (IV) for the AES decryption is the first 16 ...


7

For transactions with one input it is hard to guess what is the change and what is the real payment. However because they may be have statistics so they can may be guess that for a ~4 BTC input there are 70% of probability that the change is the bigger output and the money spent the smaller one when both output addresses are new. Now if you have a ...


7

Click "Show scripts and coinbase" to see what that output really is. In this case it's RETURN PUSHDATA(32)[8013...] RETURN (or OP_RETURN) causes the output to be unspendable. The PUSHDATA then is just a way to insert the 32 bytes 8013... into the blockchain. The significance of that data is not necessarily known to anyone except the person who created the ...


6

If a transaction returned from the http://blockchain.info/rawtx/$tx_hash endpoint has a confirmation, it will have a block_height member. You can then calculate roughly its number of confirmations by subtracting that value from the latest height retrieved from the http://blockchain.info/latestblock endpoint. Code example, in Ruby: #!/usr/bin/env ruby ...


6

My Wallet's warning for watch-only addresses ("You will not be able to send bitcoins from this address without later providing the private key") can be a bit confusing. It's possible to specify an address and watch it. And it's possible to import a private key to be able to use the associated address as if it was generated with the My Wallet client. But ...


6

www.blocktrail.com/tBTC now supports testnet too and has an API for it too (including wallet API)


6

Network propagation is the number of nodes (computers running a bitcoin client) that have heard about your transaction. Confirmations is how many blocks have included your transaction and how many blocks have linked onto that block. 1 confirmation means your transaction was included in a block, 2 confirmations means that another block linked onto that ...


6

You can add the bitcoin address to the search field at blockchain.info and you should be able to track any incoming transactions to that address. https://blockchain.info/address/1BF8SHKnT8ZysYNrj5toeu6DsuGE5XDcCR


6

From the source code, one can see that the mnemonic in fact only encodes your password and wallet identifier. You would still need to access you wallet data somehow to recover you coins.


6

Abe does exactly what you want. I will walk the entire blockchain from bitcoin-qt/bitcoind and populate a local database. It supports several database backends including sqlite, Postgres, MySQL and Oracle. It will take quite some time to walk the blockchain and populate the database, possibly a few days. It has a web based interface that is very similar to ...


6

Login to your blockchain.info wallet Select Import/Export Select Export Unencrypted Select Bitcoin-Qt Format from the drop-down list You'll then see information that look like this: "priv":"5KJvsngHeMpm884wtkJNzQGaCErckhHJBGFsvd3VyK5qMZXj3hS" Ignore the other information, what you're looking for are your private keys that look like this: ...


6

On the chart overview page you find the description "Cost per Transaction: A chart showing miners revenue divided by the number of transactions.". Meaning, it's the total value of the block reward of a block divided by the number of transactions confirmed on the network in that block. Here is an example with made up numbers: Block reward is 25 BTC + 0.1 ...


6

blk.dat files contain blocks data in raw format. Also a leveldb index is maintained that helps to quickly lookup blocks/utxo. You can find the details here and here. Blockexplorers will not directly read these files. It is not safe for multiple process to access leveldb at the same time (blockexplorer and bitcoin node process). Here is a brief summary of ...


6

The vast majority of the time, none of the 2^32 possible nonces in a particular block header template will result in the header having a hash that meets the proof-of-work target. In fact, the probability that this doesn't happen equals exactly 1 over the network difficulty. Right now, that is 1/6,379,265,451,411. When no nonce succeeds, one must change ...


6

A transaction could go unconfirmed indefinitely. The order in which transactions are confirmed is decided by miners, and generally they will be incentivized to include only the highest fee-rate transactions, to maximize their revenue. Even a low fee-rate transaction may eventually confirm, once the mempool clears out. But there is no guarantee of this, ...


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