[This post was originally posted as a Stackoverflow question.]
On 2014-09-17 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 2014-09-19. I noticed the latest 2 mails on the morning of 2014-09-20. 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 2014-09-17.
If you look at Blockchain.info Transaction 2e358fe6cd80b998eeb3f4378ab0fdbcc8d78e5898a8ebf232394a96908d84be you can see
Received Time 2014-09-20 02:41:16, not the original date
- Why have both transactions the same ID?
- Why do Blockchain.info automatically create a transaction without asking the user?
Update, 2014-09-21 11:55: The answer by amaclin seems pretty legitimately:
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.
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.