Kuusou (OP)
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November 12, 2012, 12:56:44 PM |
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Be it a computer that is offline (I understand this a bit more, the transfer of files and certificates through USB makes more sense) or a paper wallet, I am really having a hard time understanding how that works.
It would be awesome if someone could do a good job of explaining how they work (especially paper wallets) or could point me in the direction of or make an explanation video on the topic.
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Stephen Gornick
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November 12, 2012, 11:50:20 PM Last edit: November 13, 2012, 12:02:10 AM by Stephen Gornick |
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Be it a computer that is offline (I understand this a bit more, the transfer of files and certificates through USB makes more sense) or a paper wallet, I am really having a hard time understanding how that works.
It would be awesome if someone could do a good job of explaining how they work (especially paper wallets) or could point me in the direction of or make an explanation video on the topic.
![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2Fs4kv4.jpg&t=665&c=zmeHGjLTZm-tqQ) Here's the wiki article on them: - http://en.bitcoin.it/wiki/Paper_walletSimply, the private key (the "Spend" QR Code on the wallet above) is created using computer code .. javascript, in the case of BitAddress.org: - http://BitAddress.orgThat private key is needed to spend any coins sent to that Bitcoin address (the Load & Verify QR Code on the wallet above) that is derived from that private key. The computer code that will use that private key to spend needs to do a few things like determine the unspent transactions and choose one or more of them to include in a spend transaction. Blockchain.info will do this with an API call. Or you can import the private key into the Bitcoin.org client (or into your Blockchain.info/wallet, or any other client like Multibit, Electrum, etc.) and it will be treated just like any other private key in the wallet. Also you can import it into Mt. Gox and they will sweep any unspent funds for that Bitcoin address to your Mt. Gox account.
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ildubbioso
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December 12, 2012, 12:51:49 PM |
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Isn't risky sending money to an address that I can easily mistype because I have to write it on the client manually from the paper?
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Foxpup
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Vile Vixen and Miss Bitcointalk 2021-2023
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December 12, 2012, 01:04:01 PM |
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Isn't risky sending money to an address that I can easily mistype because I have to write it on the client manually from the paper? No, since Bitcoin addresses include a checksum for exactly this reason. The chance of a mistyped address being accepted as valid is 4,294,967,296 to 1.
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Will pretend to do unspeakable things (while actually eating a taco) for bitcoins: 1K6d1EviQKX3SVKjPYmJGyWBb1avbmCFM4I am not on the scammers' paradise known as Telegram! Do not believe anyone claiming to be me off-forum without a signed message from the above address! Accept no excuses and make no exceptions!
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ildubbioso
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December 12, 2012, 01:12:44 PM |
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No, since Bitcoin addresses include a checksum for exactly this reason. The chance of a mistyped address being accepted as valid is 4,294,967,296 to 1.
How does it work? I mean, if I change a letter of your address my client doesn't send the btcs?
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Foxpup
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December 12, 2012, 01:29:45 PM |
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No, since Bitcoin addresses include a checksum for exactly this reason. The chance of a mistyped address being accepted as valid is 4,294,967,296 to 1.
How does it work? I mean, if I change a letter of your address my client doesn't send the btcs? Correct. Also (in the standard client at least), when you try (and fail) to send, the address in question will be highlighted in red to indicate that is invalid.
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Will pretend to do unspeakable things (while actually eating a taco) for bitcoins: 1K6d1EviQKX3SVKjPYmJGyWBb1avbmCFM4I am not on the scammers' paradise known as Telegram! Do not believe anyone claiming to be me off-forum without a signed message from the above address! Accept no excuses and make no exceptions!
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DannyHamilton
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December 12, 2012, 03:57:40 PM |
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Isn't risky sending money to an address that I can easily mistype because I have to write it on the client manually from the paper? No, since Bitcoin addresses include a checksum for exactly this reason. The chance of a mistyped address being accepted as valid is 4,294,967,296 to 1. You can also print out QR-Codes that can be scanned with a webcam, smartphone, or document scanner to make address entry easier and less error prone.
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ildubbioso
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December 12, 2012, 05:25:24 PM |
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You can also print out QR-Codes that can be scanned with a webcam, smartphone, or document scanner to make address entry easier and less error prone.
I have done it. With a simple camera the online readers can't read my qr code. Is the quality wrong or I need a smartphone? I knew that even not perfect qr code can be read. ![](https://ip.bitcointalk.org/?u=http%3A%2F%2Fimg824.imageshack.us%2Fimg824%2F4695%2Fdscn8646b.jpg&t=665&c=SuU1XZcCdLZnCw)
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DeathAndTaxes
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Gerald Davis
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December 12, 2012, 05:29:26 PM |
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My phone was able to read that.
Adress beginning with 1Geb3w......
Looks like an issue with your phone. Does it scan other QR codes without issue? Does it have problem with some barcodes? The library may be incomplete it may have problems with certain QR code versions.
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DannyHamilton
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December 12, 2012, 05:31:01 PM |
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You can also print out QR-Codes that can be scanned with a webcam, smartphone, or document scanner to make address entry easier and less error prone.
I have done it. With a simple camera the online readers can't read my qr code. Is the quality wrong or I need a smartphone? I knew that even not perfect qr code can be read. Not sure what your issue is. I've just read your image directly from the my computer monitor with my smartphone and it worked fine. I'll try downloading it and sending it to my favorite online reader...
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DannyHamilton
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December 12, 2012, 05:33:25 PM |
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Looks like an issue with your phone.
He's not using a phone to read the QR-Code. He is using a (dumb)phone to take the picture and then sending the picture to an online QR-Decoder. With a simple camera the online readers can't read my qr code. I need a smartphone?
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Silverbug
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December 12, 2012, 05:51:12 PM |
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Wow that is really nice.
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DannyHamilton
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December 12, 2012, 05:51:47 PM |
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I tried sending your image to http://www.webqr.com/ and it was unable to read it. I opened your image with image editing software, cropped out everything that wasn't part of the code, boosted the contrast, and reduced the size by 50%. I ended up with an image which http://www.webqr.com/ was able to decode without a problem. Perhaps try for better lighting, and a lower resolution image (if your phone allows you to adjust the image capture resolution).
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ildubbioso
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December 12, 2012, 05:59:26 PM |
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I tried sending your image to http://www.webqr.com/ and it was unable to read it. I opened your image with image editing software, cropped out everything that wasn't part of the code, boosted the contrast, and reduced the size by 50%. I ended up with an image which http://www.webqr.com/ was able to decode without a problem. Perhaps try for better lighting, and a lower resolution image (if your phone allows you to adjust the image capture resolution). Thanks, I'll do it. The photo was made by a photocamera, not a phone, it's funny that I have to lower the resolution in order to read it better
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ildubbioso
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December 12, 2012, 06:02:08 PM |
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My phone was able to read that.
Adress beginning with 1Geb3w......
It seems that smartphone reads qr better than the online readers.
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DannyHamilton
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December 12, 2012, 08:57:00 PM |
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The code that you posted an image of in this discussion was the Bitcoin Address, not the Private Key. If that is what you are trying to import it won't work. NOTE: DO NOT POST AN IMAGE OF THE PRIVATE KEY OR ITS QR-CODE ANYWHERE ON THE INTERNET INCLUDING HERE. IF ANYONE ELSE HAS ACCESS TO THAT CODE THEY CAN TAKE THE COINS ASSOCIATED WITH THAT ADDRESS.Are you trying to load up a paper bitcoin with some amount of bitcoin or verify the amount that it is loaded with (in either case you need the Bitcoin Address only), or are you trying to redeem the value from a paper bitcoin into your wallet so you can spend it electronically (in which case you need the Private Key which is labeled "Spend" on the the printed paper bitcoin)?
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ildubbioso
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December 12, 2012, 11:51:28 PM |
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The code that you posted an image of in this discussion was the Bitcoin Address, not the Private Key. If that is what you are trying to import it won't work.
NOTE: DO NOT POST AN IMAGE OF THE PRIVATE KEY OR ITS QR-CODE ANYWHERE ON THE INTERNET INCLUDING HERE. IF ANYONE ELSE HAS ACCESS TO THAT CODE THEY CAN TAKE THE COINS ASSOCIATED WITH THAT ADDRESS.
I do know that I didn't posted the private key ![Wink](https://bitcointalk.org/Smileys/default/wink.gif) are you trying to redeem the value from a paper bitcoin into your wallet so you can spend it electronically (in which case you need the Private Key which is labeled "Spend" on the the printed paper bitcoin)?
Yes. And I used the instructions on the wiki. But I had the code 4 error.
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DannyHamilton
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December 13, 2012, 12:06:46 AM |
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are you trying to redeem the value from a paper bitcoin into your wallet so you can spend it electronically (in which case you need the Private Key which is labeled "Spend" on the the printed paper bitcoin)?
Yes. And I used the instructions on the wiki. But I had the code 4 error. Odd. I suspect there is something wrong in the importprivkey command parameters you used, but I'm not sure what. Generally when in wallet import format the private key will be start with a 5 and will be 51 characters long. Perhaps you had a copy/paste error when trying to get the private key to the command from the QR-Reader? You might want to double check the private key you used in the importprivkey command and compare it to the one from the QR-Code (or printed on the paper). Assuming that you were trying to import the following private key: 5Kb8kLf9zgWQnogidDA76MzPL6TsZZY36hWXMssSzNydYXYB9KF Your command should look like this: importprivkey 5Kb8kLf9zgWQnogidDA76MzPL6TsZZY36hWXMssSzNydYXYB9KF "Testing import" Nothing else extra, nothing missing. If your wallet is encrypted with a password, you'll need to provide the password before you'll be able to run that command. That is the purpose of the command: walletpassphrase "YourLongPassphrase" 600 The 600 indicates that the wallet private keys are to remain unlocked for the next 10 minutes (600 seconds). If none of this helps, then you'll need to wait for someone more knowledgeable than me to discover this discussion. You may want to try posting a question about this over in one of the "Technical" fourms ("Technical Support" or "Technical Discussion"). You might have a better chance of finding someone who can help.
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casascius
Mike Caldwell
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The Casascius 1oz 10BTC Silver Round (w/ Gold B)
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December 13, 2012, 12:23:52 AM |
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Thanks, I'll do it. The photo was made by a photocamera, not a phone, it's funny that I have to lower the resolution in order to read it better.
My guess is lowering the resolution removes the white streaks that cut through all the blocks due to the print quality. BlockChain.info's private key import works really well and you can spend the funds instantly upon import. They also have a webcam-based QR code scanner right in their website.
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Companies claiming they got hacked and lost your coins sounds like fraud so perfect it could be called fashionable. I never believe them. If I ever experience the misfortune of a real intrusion, I declare I have been honest about the way I have managed the keys in Casascius Coins. I maintain no ability to recover or reproduce the keys, not even under limitless duress or total intrusion. Remember that trusting strangers with your coins without any recourse is, as a matter of principle, not a best practice. Don't keep coins online. Use paper or hardware wallets instead.
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