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Bitcoin => Bitcoin Technical Support => Topic started by: renner123 on October 29, 2020, 06:34:26 PM



Title: cancel old transaction / update my blockchain?
Post by: renner123 on October 29, 2020, 06:34:26 PM
 Hello,

I have executed a transaction from Wallet A (Bitcoin Core) to Wallet B in early 2018 (my block chain was 3 years behind at that time).

The amount has never been credited to Wallet B. After research at blockchain.info the transaction ID (0 transaction confirmations) is not available and the exact amount is still assigned to Wallet A. Only my credit there does not show this sent amount.

Since my blockchain hasn't been updated since then and is therefore almost 5 years in behind, I would like to know what happens if I run the update? Would the transaction still be executed or not? Would there be a way to cancel the transaction?

Thanks a lot.



Title: Re: cancel old transaction / update my blockchain?
Post by: LoyceV on October 29, 2020, 06:43:19 PM
Since my blockchain hasn't been updated since then and is therefore almost 5 years in behind, I would like to know what happens if I run the update? Would the transaction still be executed or not?
If your Bitcoin Core is still trying to broadcast it, that might actually happen. I've never waited this long, but I've also never seen Bitcoin Core stop broadcasting a transaction before it's confirmed.

Quote
Would there be a way to cancel the transaction?
First: backup your wallet.dat!
Then, use zapwallettxes (https://bitcoin.stackexchange.com/questions/45988/how-do-you-apply-zapwallettxes-on-windows):
Code:
  -zapwallettxes=<mode>
       Delete all wallet transactions and only recover those parts of the
       blockchain through -rescan on startup (1 = keep tx meta data e.g.
       account owner and payment request information, 2 = drop tx meta
       data)


Title: Re: cancel old transaction / update my blockchain?
Post by: AB de Royse777 on October 29, 2020, 06:43:51 PM
Wallet update is not going to affect the blockchain. A blockchain is keeping the record of all transaction which do not have any connection with any wallet client.

What I understand from reading you post is that your core wallet never sent the coin to your blockchain wallet hence the coin never reached there and it was always in the core wallet. If you know the address of the coin then use any block explorer and see it's there.

PS: I am assuming that you have not sent the coins to a wrong address since you said the coins were there (core).


Title: Re: cancel old transaction / update my blockchain?
Post by: renner123 on October 29, 2020, 06:56:04 PM

PS: I am assuming that you have not sent the coins to a wrong address since you said the coins were there (core).

Yes, if I check my wallet A address at blockchain.com the stated balance is the exact amount the shoud have been sent years ago, but the wallet at my bitcoin core client says balance = 0.

I have access to wallet A (my PC) and wallet B (online wallet).

So canI update my client without any danger?


Title: Re: cancel old transaction / update my blockchain?
Post by: AB de Royse777 on October 29, 2020, 07:08:43 PM
So canI update my client without any danger?
Not sure after reading LoyceV's response but my basic instinct is saying that you should be safe. I do not see any reason for a client to start broadcasting a tx that was made long time ago and never was broadcasted.

Do you know the private key of the wallet? Assuming you do. In that case try to restore the wallet using Electrum  (https://electrum.org/#download)and once you see the balance then send them to another wallet (fees are too high right now which sucks by the way). So once the address is empty (make sure the tx has minimum 1 confirmation), then try to restore the wallet using your core client. This is the safest practice I can think off now.

PS: Make sure you have verified the signature of the downloaded Electrum client. Here is a tutorial if needed : https://bitcoinelectrum.com/how-to-verify-your-electrum-download/

Edit:
Quote
but the wallet at my bitcoin core client says balance = 0.
The reason is that the client has not synchronized in full yet.


Title: Re: cancel old transaction / update my blockchain?
Post by: BitMaxz on October 29, 2020, 07:26:56 PM
~snip~

What do you want exactly?
Are you trying to cancel the transaction?

If you are going to update the blockchain may be the unconfirmed transaction that you made before might broadcast again. So if you don't want to send it to "wallet B" you can able to remove it from "wallet A" by following LoyceV's suggestion above it should be work.

And it's recommended to cancel or remove the transaction from your wallet if your transaction is paid with a low fee due to network congestion and we don't have any idea of what online wallet you used with "wallet B"?


Title: Re: cancel old transaction / update my blockchain?
Post by: renner123 on October 29, 2020, 07:29:29 PM
So canI update my client without any danger?
Not sure after reading LoyceV's response but my basic instinct is saying that you should be safe. I do not see any reason for a client to start broadcasting a tx that was made long time ago and never was broadcasted.

Do you know the private key of the wallet? Assuming you do. In that case try to restore the wallet using Electrum  (https://electrum.org/#download)and once you see the balance then send them to another wallet (fees are too high right now which sucks by the way). So once the address is empty (make sure the tx has minimum 1 confirmation), then try to restore the wallet using your core client. This is the safest practice I can think off now.

PS: Make sure you have verified the signature of the downloaded Electrum client. Here is a tutorial if needed : https://bitcoinelectrum.com/how-to-verify-your-electrum-download/

Edit:
Quote
but the wallet at my bitcoin core client says balance = 0.
The reason is that the client has not synchronized in full yet.

Thank you for your help so far.

Yes, I have the private key. And my wallet.dat on my pc. I don't understand why I should restore this wallet and make another transaction. Sorry, but could you explain this for a 5 year old? Thank you.

PS: Wallet B is a litbit.eu online wallet

My goal is it to cancel the tx and store the BTC on a more safer place than wallet B


Title: Re: cancel old transaction / update my blockchain?
Post by: AB de Royse777 on October 29, 2020, 07:50:58 PM
Yes, I have the private key. And my wallet.dat on my pc. I don't understand why I should restore this wallet and make another transaction. Sorry, but could you explain this for a 5 year old? Thank you.
Remember wallet.dat will not work with Electrum, you will need the private key to resotre the wallet if you chose Electrum.

The reason for my suggestion is to move the coins from your current address - (My understanding) if you move the coins and then if you want to sync your bitcoin core wallet and if this has the old tx which was waiting for broadcasting, will not broadcast since the wallet balance will be zero.

Anyway, what I understand is that you want to move the coins to another safe wallet. Which you can do using the method I suggested. You will not need Bitcoin core for that.  From the restored wallet (Electrum) send the coins to your desired address. Should be very simple job by the way.


Title: Re: cancel old transaction / update my blockchain?
Post by: hosseinimr93 on October 29, 2020, 08:02:51 PM
Then, use zapwallettxes (https://bitcoin.stackexchange.com/questions/45988/how-do-you-apply-zapwallettxes-on-windows):
I don't think the command written in that thread works. Must add quotation marks at the start and end of the file path.
The command must be as follows.

Code:
"C:\Program Files (x86)\Bitcoin\bitcoin-qt" --zapwallettxes=1


Title: Re: cancel old transaction / update my blockchain?
Post by: renner123 on October 29, 2020, 08:10:29 PM
I just tried the -zapwallettxes and the full amount is now displayed in my wallet A (on my PC) again (and I doubled my networth).  Thank you guys! Now I have to find a way to store the BTC in the most safest way.


Title: Re: cancel old transaction / update my blockchain?
Post by: LoyceMobile on October 29, 2020, 08:16:53 PM
Now I have to find a way to store the BTC in the most safest way.
Ledger or Trezor hardware wallet is probably the easiest and most n00b friendly.

After moving your Bitcoin, you may want to check for Forkcoins you own. As always on crypto: don't do anything before you understand what you're doing.


Title: Re: cancel old transaction / update my blockchain?
Post by: BitMaxz on October 29, 2020, 09:12:10 PM
I just tried the -zapwallettxes and the full amount is now displayed in my wallet A (on my PC) again (and I doubled my networth).  Thank you guys! Now I have to find a way to store the BTC in the most safest way.

That's good because if it was broadcasted again you might lose your bitcoin because this domain "litbit.eu" it seems it's not available anymore the site leads me to a paxful site with referral.

Alternative for hardware wallet as LoyceV suggested above you can use Electrum as another option if you don't have hardware wallet yet.
Use this official Electrum site https://electrum.org/ and be careful to any fake Electrum website.

For safety verify the Electrum first before you install you can follow this guide "How to verify Electrum (for Windows, Linux and Mac) (https://bitcointalk.org/index.php?topic=5105901.0)"


Title: Re: cancel old transaction / update my blockchain?
Post by: AB de Royse777 on October 30, 2020, 08:55:08 AM
Good to hear the good news renner123.

Now about storing safely, I will suggest the same as BitMaxz in the post above but with some additional security step. However a hardware wallet is easier if you find it hard of course.

You will need two devices. One will never go online that will have your wallet stored. You can write up the seeds and always delete the wallet after making a transaction on the offline device if this was being used for any other task by any other family member but make sure this never goes online. In the online device you will have a watch only wallet using the master public key of the wallet from offline device.

Whenever you will need to broadcast a transaction:
- You will create the tx from the online device then export the file.
- Using a USB stick or other removable disk take the file and from the offline device load the tx and sign it. Then export the signed tx and save it in the removable disk.
- Load the signed tx in the online device, online watch only wallet and broadcast the tx.

This way your wallet is never going online and you have zero risk of getting caught by any malware or hacking of your wallet.

In the offline device, the balance will show zero always by the way. The reason is - it was never online and was never been able to sync with the blockchain. You will always see the up to date data in the watch only device by the way.

For safety verify the Electrum first before you install you can follow this guide "How to verify Electrum (for Windows, Linux and Mac) (https://bitcointalk.org/index.php?topic=5105901.0)"
And please do not skip this step before installing the software. @renner123