About double spending | Bitcointalksearch.org

Muhammed Zakir

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Quote from: locopao on May 27, 2015, 05:23:18 AM

Actually is not a blockchain wallet. It's a multibit wallet address and i clicked on a previous transaction to see the details on blockchain and then i saw the above message.

It will appear if you receive any double-spent Bitcoin regardless of the wallet you use.

Quote from: locopao on May 27, 2015, 05:23:18 AM

So you think it will stop showing after a while?

(AFAIK) if one of the transactions which use same input is dropped, it will be gone. If not, then Blockchain.info should fix this.

Quote from: locopao on May 27, 2015, 05:23:18 AM

There is one more thing:
A few days ago i sent some coins from one address to another, in the same wallet (multibit), just for testing purposes (to see if i can send between my addresses inside the same wallet).

You think this is why i get this message?

Thanks!

Maybe. If input in that transaction was already spent or if you spent it later.

Quote from: locopao on May 27, 2015, 07:42:04 AM

Quote from: KarmaShark on May 27, 2015, 06:07:55 AM

Did you transferred the money between wallet without fees ?
I think you probably did and that's the reason it appeared.
I never had such experience ,so no idea on fixing it.
Good luck

hmmm

not sure, but i think i have set a fee by default, so any transaction will go out with the minimum fee.
-snip-

No. Sending a zero fee transaction doesn't make this warning appear in bc.io. It appears *only* if you receive any double-spending transaction.

Quote from: twister on May 27, 2015, 01:48:48 PM

-snip-
but it showed the warning message when I checked it on the blockchain.info site, which you described above but it did went away after a day I think.

The double-spent Bitcoin you received may have dropped and the warning went away.

Quote from: twister on May 27, 2015, 01:48:48 PM

So my guess it will go away on it's own in a day or two.

It's permanent like redsn0w told but (AFAIK) if one of the transactions which use same input is dropped, it will be gone. If not, then Blockchain.info should fix this.

twister

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Quote from: redsn0w on May 27, 2015, 01:52:55 PM

Quote from: twister on May 27, 2015, 01:48:48 PM

I once got this message too but here's how it happened with me. I was using Blockchain.info and Electrum wallet. So I had some coins in the blockchain wallet and I tried sending them, it showed sent but they didn't hit the blockchain, I entered the Tx ID at several blockchain sites to check but nothing, so I panicked and thought maybe it's getting hacked.

Immediately after that I exported the key out of blockchain and imported it into my electrum and pushed the transaction and it went through but it showed the warning message when I checked it on the blockchain.info site, which you described above but it did went away after a day I think. So my guess it will go away on it's own in a day or two.

No, that warning will stay "for ever" or at least it will continue to appera on blockchain.info blockexplorer but not in the other BTC blockExplorer. A double spend it is an easy thing, and now a lot of people start to do it (with the use of the replace-by-fee function and a little bit of lucky).

In my case it did went away the next day, maybe they changed it to remain permanently now, I don't know since that was the only time I witnessed it. Maybe as you say it is an easy thing but I still have no idea how to do it and don't even want to know.

redsn0w

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Quote from: twister on May 27, 2015, 01:48:48 PM

I once got this message too but here's how it happened with me. I was using Blockchain.info and Electrum wallet. So I had some coins in the blockchain wallet and I tried sending them, it showed sent but they didn't hit the blockchain, I entered the Tx ID at several blockchain sites to check but nothing, so I panicked and thought maybe it's getting hacked.

Immediately after that I exported the key out of blockchain and imported it into my electrum and pushed the transaction and it went through but it showed the warning message when I checked it on the blockchain.info site, which you described above but it did went away after a day I think. So my guess it will go away on it's own in a day or two.

No, that warning will stay "for ever" or at least it will continue to appera on blockchain.info blockexplorer but not in the other BTC blockExplorer. A double spend it is an easy thing, and now a lot of people start to do it (with the use of the replace-by-fee function and a little bit of lucky).

twister

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I once got this message too but here's how it happened with me. I was using Blockchain.info and Electrum wallet. So I had some coins in the blockchain wallet and I tried sending them, it showed sent but they didn't hit the blockchain, I entered the Tx ID at several blockchain sites to check but nothing, so I panicked and thought maybe it's getting hacked.

Immediately after that I exported the key out of blockchain and imported it into my electrum and pushed the transaction and it went through but it showed the warning message when I checked it on the blockchain.info site, which you described above but it did went away after a day I think. So my guess it will go away on it's own in a day or two.

locopao

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Quote from: KarmaShark on May 27, 2015, 06:07:55 AM

Did you transferred the money between wallet without fees ?
I think you probably did and that's the reason it appeared.
I never had such experience ,so no idea on fixing it.
Good luck

hmmm

not sure, but i think i have set a fee by default, so any transaction will go out with the minimum fee.

On the other hand i don't think it'a a big deal, the transaction was 0.012 from one address to another, and the receiving address shows this amount properly. The sending address is the one that shows this message.

Anyway, thanks for checking.

KarmaShark

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Edited out instructions / feedback.

Good luck

locopao

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Quote from: notlist3d on May 27, 2015, 04:17:14 AM

I believe with block chain it will stop after a certain amount of hours. It might try a second time though.

As far as double spend it's not going to be possible on blockchain wallet. You would have to import key into a different wallet that is able to double spened.

Actually is not a blockchain wallet. It's a multibit wallet address and i clicked on a previous transaction to see the details on blockchain and then i saw the above message.

So you think it will stop showing after a while?

There is one more thing:
A few days ago i sent some coins from one address to another, in the same wallet (multibit), just for testing purposes (to see if i can send between my addresses inside the same wallet).

You think this is why i get this message?

Thanks!

notlist3d

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I believe with block chain it will stop after a certain amount of hours. It might try a second time though.

As far as double spend it's not going to be possible on blockchain wallet. You would have to import key into a different wallet that is able to double spened.

locopao

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When i check my address through blockchain.info, i see this message:

"Warning! this bitcoin address contains transactions which may be double spends. You should be extremely careful when trusting any transactions to or from this address."

My question is How can i check which is/are the transactions the message refers to? And how can i fix this?

By the way, i use this address only for payments from my signature.

Topic: About double spending (Read 679 times)