<p>You do not understand correctly how does bitcoin network work. Your first transaction was sent to a network and will live there until all it is valid or all nodes forget about it.</p>

<p>Blockchain.info just notifies you that it was not confirmed into a block in reasonable time. Blockchain.info removed it from its memory, but there are nodes on the network which do not forget about it and one of them broadcasted this transaction to its peers.</p>

<blockquote>
  <p>Why have both transactions the same ID?</p>
</blockquote>

<p>These are not two transactions. This is one transacton, received by blockchain.info twice. First time you sent it. Second time blockchain.info received it fron one of peers.</p>

<blockquote>
  <p>Why do Blockchain.info automatically create a transaction without asking the user?</p>
</blockquote>

<p>They did not.</p>

CC BY-SA 3.0
2014-09-21T13:20:30.790Z
I see. Thank you! So Blockchain.info completely delete a transaction from their system without any trace.
TheFox
CC BY-SA 3.0
2014-09-21T15:44:19.347Z
@TheFox No, BCI gets your txn and propagates it to the network amongst many nodes. BCI would have flagged your txn for having no fees and seeing it was not included in a block (ie processed) after an arbitrary period of time BCI decided it was unlikely to be processed by the network so it removed the txn request from it's pushed txn Api database and in doing so, automatically emailed the assumption of a refund. Not long afterwards a node **has** included your txn in a mined block & relayed it to BCI; the notification of this completed txn is independent of the assumption it wouldn't be filled
Wizard Of Ozzie
CC BY-SA 3.0
2014-09-21T16:25:27.410Z
This particular transaction is not in block! Because of low fee. In a couple of days blockchain.info will forget about it again, but it is possible that somebody will send this transaction to blockchain.info again :) The only possiblility to stop this process is spending this UTXO with another transaction :)
amaclin
CC BY-SA 3.0
2014-09-21T16:43:07.790Z
But why does BCI not keep the TX? If every node knows that the transaction is invalid or not included to a block they could keep the transaction and don't inform the user about the same transaction a second time. This makes no sense. If I don't know the ID of the *first* transaction the *second* transaction appears to me like a *new* transaction, even if it's still the same transaction. It's not user friendly. It's confusing for user who doesn't understand the Bitcoin system in depth. Most user only want do buy something with Bitcoins but not unterstand the system in depth.
TheFox
CC BY-SA 3.0
2014-09-21T16:52:58.920Z
This transaction is valid. And it can be included in block. But no miner wants to do it. Blockchain.info can not keep all such transaction for an infinite time.
amaclin
CC BY-SA 3.0
2014-09-21T11:55:33.277Z
2014-09-21T11:55:33.277Z
amaclin
<p>On Sep 17 I wanted to transfer 0.001 BTC from one Blockchain.info account (bitcoin address 1BFFtYPgtaZUHujDqiehqSseZvuUzJQxki) to another Blockchain.info account (bitcoin address 1DE4VjkipjVEoevVJCpLQARZcYdDvZgcow): transaction 2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be.</p>

<p>I got an email notification about this transaction:</p>

<blockquote>
  <p>Subject: Bitcoin Payment Received<br>
  Date: Wed, 17 Sep 2014 18:41:17 +0000 (UTC)  </p>
  
  <p>Payment Received Notification<br>
  A Payment has been received into your bitcoin wallet.<br>
  2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be<br>
  1BFFtYPgtaZUHujDqiehqSseZvuUzJQxki -> 1DE4VjkipjVEoevVJCpLQARZcYdDvZgcow 0.001 BTC</p>
</blockquote>

<p>Some days later I got the following email:</p>

<blockquote>
  <p>Subject: Bitcoin Transaction Failed<br>
  Date: Fri, 19 Sep 2014 19:03:34 +0000 (UTC)  </p>
  
  <p>Transaction Confirmation Failed
  A transaction made through Blockchain.info has been removed from our database because it was taking a long time to be included in a block.<br>
  Any funds have been returned to your wallet and you can now spend the coins again. Please consider including a larger fee in future transactions.</p>
</blockquote>

<p>This happend because I have not included any transaction fee, I know. But I also got this email:</p>

<blockquote>
  <p>Subject: Bitcoin Payment Received<br>
  Date: Sat, 20 Sep 2014 02:41:23 +0000 (UTC)  </p>
  
  <p>Payment Received Notification<br>
  A Payment has been received into your bitcoin wallet.<br>
  2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be<br>
  1BFFtYPgtaZUHujDqiehqSseZvuUzJQxki -> 1DE4VjkipjVEoevVJCpLQARZcYdDvZgcow 0.001 BTC</p>
</blockquote>

<p>I took no action on the evening of Sep 19. I noticed the latest 2 mails on the morning of Sep 20. This new transaction was created automatically by Blockcain.info. Since the second email said <code>A transaction made through Blockchain.info has been removed from our database [...]</code> I thought the transaction has been deleted but the new transaction ID is the same as on Sep 17.</p>

<p>If you look at <a href="https://blockchain.info/tx/2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be" rel="nofollow">Blockchain.info Transaction 2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be</a> you can see <code>Received Time 2014-09-20 02:41:16</code>, not the original date <code>2014-09-17</code>.</p>

<ul>
<li>Why have both transactions the same ID?</li>
<li>Why do Blockchain.info automatically create a transaction without asking the user?</li>
</ul>

<transactions><transaction-fees><blockchain.info><transaction-verification>
Blockchain.info automatic transaction
TheFox
# Blockchain.info automatic transaction

(Asked by: username_0 on 2014-09-21)

On Sep 17 I wanted to transfer 0.001 BTC from one Blockchain.info account (bitcoin address 1BFFtYPgtaZUHujDqiehqSseZvuUzJQxki) to another Blockchain.info account (bitcoin address 1DE4VjkipjVEoevVJCpLQARZcYdDvZgcow): transaction 2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be.

I got an email notification about this transaction:

> Subject: Bitcoin Payment Received  
> Date: Wed, 17 Sep 2014 18:41:17 +0000 (UTC)
>
> Payment Received Notification  
> A Payment has been received into your bitcoin wallet.  
> 2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be  
> 1BFFtYPgtaZUHujDqiehqSseZvuUzJQxki -> 1DE4VjkipjVEoevVJCpLQARZcYdDvZgcow 0.001 BTC

Some days later I got the following email:

> Subject: Bitcoin Transaction Failed  
> Date: Fri, 19 Sep 2014 19:03:34 +0000 (UTC)
>
> Transaction Confirmation Failed
> A transaction made through Blockchain.info has been removed from our database because it was taking a long time to be included in a block.  
> Any funds have been returned to your wallet and you can now spend the coins again. Please consider including a larger fee in future transactions.

This happend because I have not included any transaction fee, I know. But I also got this email:

> Subject: Bitcoin Payment Received  
> Date: Sat, 20 Sep 2014 02:41:23 +0000 (UTC)
>
> Payment Received Notification  
> A Payment has been received into your bitcoin wallet.  
> 2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be  
> 1BFFtYPgtaZUHujDqiehqSseZvuUzJQxki -> 1DE4VjkipjVEoevVJCpLQARZcYdDvZgcow 0.001 BTC

I took no action on the evening of Sep 19. I noticed the latest 2 mails on the morning of Sep 20. This new transaction was created automatically by Blockcain.info. Since the second email said `A transaction made through Blockchain.info has been removed from our database [...]` I thought the transaction has been deleted but the new transaction ID is the same as on Sep 17.

If you look at [Blockchain.info Transaction 2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be](https://blockchain.info/tx/2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be) you can see `Received Time 2014-09-20 02:41:16`, not the original date `2014-09-17`.

* Why have both transactions the same ID?
* Why do Blockchain.info automatically create a transaction without asking the user?

**Tags:** transactions, transaction-fees, blockchain.info, transaction-verification


---

## 1 answers

### Answer by username_1 on 2014-09-21. Score: 1 | Accepted answer

You do not understand correctly how does bitcoin network work. Your first transaction was sent to a network and will live there until all it is valid or all nodes forget about it.

Blockchain.info just notifies you that it was not confirmed into a block in reasonable time. Blockchain.info removed it from its memory, but there are nodes on the network which do not forget about it and one of them broadcasted this transaction to its peers.

> Why have both transactions the same ID?

These are not two transactions. This is one transacton, received by blockchain.info twice. First time you sent it. Second time blockchain.info received it fron one of peers.

> Why do Blockchain.info automatically create a transaction without asking the user?

They did not.

> **Comments:**
> **username_0**: I see. Thank you! So Blockchain.info completely delete a transaction from their system without any trace.  
> **username_2**: @username_0 No, BCI gets your txn and propagates it to the network amongst many nodes. BCI would have flagged your txn for having no fees and seeing it was not included in a block (ie processed) after an arbitrary period of time BCI decided it was unlikely to be processed by the network so it removed the txn request from it's pushed txn Api database and in doing so, automatically emailed the assumption of a refund. Not long afterwards a node **has** included your txn in a mined block & relayed it to BCI; the notification of this completed txn is independent of the assumption it wouldn't be filled  
> **username_1**: This particular transaction is not in block! Because of low fee. In a couple of days blockchain.info will forget about it again, but it is possible that somebody will send this transaction to blockchain.info again :) The only possiblility to stop this process is spending this UTXO with another transaction :)  
> **username_0**: But why does BCI not keep the TX? If every node knows that the transaction is invalid or not included to a block they could keep the transaction and don't inform the user about the same transaction a second time. This makes no sense. If I don't know the ID of the *first* transaction the *second* transaction appears to me like a *new* transaction, even if it's still the same transaction. It's not user friendly. It's confusing for user who doesn't understand the Bitcoin system in depth. Most user only want do buy something with Bitcoins but not unterstand the system in depth.  
> **username_1**: This transaction is valid. And it can be included in block. But no miner wants to do it. Blockchain.info can not keep all such transaction for an infinite time.  

---

