Something very strange happened today. blockchain.info let me send 1.48 BTC when I only had 0.6. I had a incoming transaction of 1 BTC. For some reason it made the sending transaction twice (received and sent BTC in the same block) and it is displayed as unconfirmed and my balance is negative.
screenshot:
Can I remove the unconfirmed transaction? Why did it send twice?
screenshot:
Can I remove the unconfirmed transaction? Why did it send twice?
It did not send it twice, but the transaction you send (A) was modified along the way by a node. This create transaction B that spends the same coins and sends them to the same address as A, but has a different transaction ID. This is called a "malleabiltiy attack" and can be fixed by contacting blockchain.infos support. Only A or B can confirm never both.
More here -> https://bitcointalk.org/index.php?topic=1198032.0