Topic: Only got the old wallets address, possible to use it? (Read 516 times)

Bitcoin core is a full node. This means it will download, verify and store the whole blockchain. And this takes time.
With a SPV wallet, your client is connecting to a server (which has the whole blockchain) and asks them about your transactions/addresses.  Note that it is a bit more complex like that, i.e. the server can not simply "lie".

If you don't want to rely on any 3rd party, you need to run your own full node (which takes time to synchronize). If you just want to "use" BTC, a SPV wallet is sufficient.

You can't get all your transaction information if you don't synchronize it. SPV wallet or not, you're still synchronizing your wallet. It's just that SPV wallets are way faster than Bitcoin Core due to the fact that SPV wallets only download the block headers. You can't use a wallet without synchronization because you'll likely get outdated information which wouldn't allow you to spend your coins.

Thank you, so whats the reason with synching when you can use it directly instead?

That's the process of downloading and verifying the blockchain on your own computer a.k.a. full node.
Once you are up-to-date with the current network, your node is synced (with the network).




It is, if you decide to import your private keys into a different (SPV) wallet.
If you want to send a transaction from core, it needs to be synced first.

But you are free to export the private keys and import (or sweep) them into another wallet. For this, your node does not need to be synced.

Thank you for response.
What is the meaning of syncing it? I mean whats the good stuff syncing it instead of just send it? Is it even possible to send it without synching it beforehand? If you compere it with import/sweep in into another application?

It won't matter if it was synced on the old one or not... when you have the new computer and new client setup and fully synced, you'll be able to see everything as required.


Yes, that should be fine... you will just need to make sure that you don't forget that passphrase, as it will be required to send coins from that wallet.dat now.




If you have a look here: https://jochen-hoenicke.de/queue/#0,2w

You can see the last 2 weeks worth of activity... you'll note that generally, the mempool is relatively "empty" and the fees are generally lower on "weekends"...  Having said that, if you look at the "30d" chart, you'll notice things were just crazy during the end of Oct... and even on weekends the mempool was quite full and the fees were quite high. So, it's not guaranteed, and a big bull run or price dump can mean lots of extra activity, even on weekends... but weekends tend to be quieter and the fees lower.

Just check the website, when you're considering sending, and you'll get a quick snapshot of how "busy" things are etc.

But we are goin to import it to the new client on the new computer, it were never synced completed on the old one. It still possible to import it? And its the sam thing in the end?

"How exactly did you encrypt it? Did you add a passphrase to it using the "Settings -> Encrypt wallet" menu option within Bitcoin Core?"

Yes, we did it that way. That should be alright?






Alright, some days that are more optimal than others?




Thank you !

Yes, once Bitcoin Core is fully synced, you can shut it down... then copy the old wallet.dat into the Bitcoin Coin "data directory". You can find the data directory by looking in the "Window -> Information" menu... look for the "Datadir" value:


Once you've copied the wallet.dat into that directory, you can simply restart Bitcoin Core and it will automatically use this wallet.dat.

NOTE: if the file is not called exactly "wallet.dat", once you have restarted Bitcoin Core, you'll need to use the "File -> Open wallet" menu and select the .dat file that you copied into the datadir.


How exactly did you encrypt it? Did you add a passphrase to it using the "Settings -> Encrypt wallet" menu option within Bitcoin Core? or did you use some external form of encryption?


Network fees are always dependent on a number of things, data size of the transaction, current network conditions etc... if the wallet contains lots and lots of tiny amounts, it'll make any transaction you create larger than normal and the total fee required will be more than normal. If the network is busy, you don't necessarily need to send with a large fee, but you'll end up waiting for a number of hours to get the transaction confirmed.

In any case, Bitcoin Core allows you to customise the fee rates to your liking... you can easily send using the minimum amount of 0.00001000 BTC/kB if you want (that is the equivalent of 1 sat/byte). You just need to be aware that this could mean it takes a while for the transaction to get included in a block if the network is busy and fee rates are "high".

Usually, it takes from 1day to two weeks (or more) depending on the PC.
It's mostly based from your internet speed next is your machine's specs.
To speed things up, I'd suggest you to increase the dbcache to at least half of your RAM.
The option is in "Settings->Options->Size of Database Cache".

For the fee, you can time it right when there are a few transactions in the network, you can use this site to check if the average fee/mempool size is low:
https://jochen-hoenicke.de/queue/#0,2h

Thank you for your answers. We decided we should chose the option of using bitcoin core on a new safe computer and import the dat-file from there. Since I am helping my friend by the phone, it would be great to know as much as possible before we start. We have some time since the downloading process of bitcoin core is pretty time consuming. Is there a function in the newer version of the program that we could be using in an easy way or do we have to replace files and such?

We have encrypted the dat-file from the old computer btw, so it feels much better to import it in the new one.

After that I guess the wallet will continue the sync, how long would that take? And after that the next thing would be to send it to a new wallet, right? Any good recommendations for not having to pay a high fee?

What exactly do you want to achieve?

Do you want to access your coins as fast as possible?
If so, and you are sure that all the coins from your wallet are only on that one address: Import the private key into another wallet (e.g. electrum).

Do you want to switch your wallet so you don't need to keep the whole blockchain synced?
Wait for it to be synced and send a transaction containing everything to a new wallet created in a SPV client (e.g. electrum).

Do you just want to be able to send your coins and don't mind or explicitly want to store and verify the blockchain?
Then, wait for core to be fully synced.

I didn't mean to make it sound like it's likely to get it infected, but I generally avoid moving crypto-related stuff through removable storage devices such as USBs and MicroSD cards. At one point, it's possible that you may not wipe the USB correctly and plug it into an infected PC while still containing your .dat file.

I don't see it as a problem now, but for the longer-term. Once you get used to the convenience of moving files through USB from one device to another, you get to prefer doing that rather than safer methods.

That's great. The private key is enough for your backup, but it's certainly not bad to also have the wallet address written next to it.

By using that option, you'd only import the private key inside your wallet. As in, you'd only have an Electrum wallet with a single address in it that you can use.

No, importing the ".dat" file and importing the privkey are two different things. AFAIK, the privkey is part of the ".dat" file. It's the access to a single Bitcoin address that you've exported from your old Bitcoin Core wallet.

By the way, are you sure you only have a single address that you've used on your old Bitcoin Core wallet? You can generate multiple receiving addresses, so make sure you backed up the good one(s).

No. If you enter just the address, you will create a watch-only wallet. You can watch anyone's wallet - even mine. If you insert my Bitcoin address in there, you could see my txs, my balance etc. but you do not have access to spend from my address. It's like I'd show you a number of physical banknotes. You can see them, you can count them, but you can't use them because they're mine.

In there you only have to insert the private key. As I said above, the privkey is enough to recover your funds.

Assuming it's a new PC, the sync will not "continue" from the point your old PC's Bitcoin Core has reached. It would just start from zero instead. But as I mentioned, when you use Electrum, unless you're running a full node (downloading and syncing the entire blockchain, like you had to do with Bitcoin Core), the sync will only take a few seconds. It's running in light mode by default, which means you don't need a lot of storage and time to sync it.

But in all honesty, considering that you are quite new to this stuff, I would rather recommend either sweeping all the private key(s) or fully syncing the Bitcoin Core wallet as @HCP suggested above and having your entire balance be up-to-date before actually moving funds out. You may have other receiving addresses you've used before and still have balance in them. May take more time, but better be safe than sorry.

You're already using a non-encrypted wallet.dat,
it's basically a collection of unencrypted private keys that're ready to be taken anytime if your machine isn't secured.

In terms of "danger", you are already at the red zone.

Risks and to do's:

• The basics: do not share the wallet file, private key(s); "hdseed" and "extended private masterkey" from the wallet dump file.
• If you're planning to sync Bitcoin core, at least encrypt your wallet.dat and make another backup after; there will be a warning about it if you try to encrypt the wallet.
• Keep the old backup safe in an offline storage for insurance
• Make sure to verify the signature of the wallet that you're going to use before using or importing anything in it.

Correct. Once Bitcoin Core finishes syncing, it will show all the transaction history and correct balance. The issue being that syncing Bitcoin Core can take a "long time"™ as it needs to download and verify the entire blockchain which is currently 350+gigs worth of data.

This is also the "safest" option, as there is no need to expose private keys which you can potentially do when using export/import etc.

Sort of... if you're exporting/importing individual keys, there is a possibility that you might "miss" one... Bitcoin Core actually has 100's of private keys stored in the wallet.dat and it also uses "change" addresses (when spending coins), which you won't necessarily "see" in the application as they tend to be "hidden", but still a possibility that one of them contains some of your funds if you've ever sent coins from that wallet.

So, when exporting/importing individual keys to another app, it might not necessarily be an exact clone of the original wallet. However, if you simply copy the entire wallet.dat and open it with another copy of Bitcoin Core, it will be an exact clone.



No, you don't use WALLET_ADDRESS, you don't even need the WALLET_ADDRESS... Electrum will automagically derive the address from the private key...

So, in that window where it says "Enter a list of Bitcoin addresses (this will create a watching-only wallet), or a list of private keys.", you put:

The private key should start with a "K", "L" (or possibly a "5" if it is VERY old)


It isn't necessarily inherently "dangerous" per se... but more that it carries more "risk"... If you have unknown malware/keyloggers infecting your computer, they could detect private keys being copied to the clipboard or typed on the keyboard or even detected by a "screengrabber" that sends screenshots to the hackers etc.


If you have the time, the bandwidth and the available storage on your harddrive, I would personally recommend that you simply let Bitcoin Core finish syncing, then you can use it to safely send the funds wherever you want. You won't have to worry about potentially exposing to private keys to any unnecessary risk and you can be sure that you are seeing "total" balance contained within the wallet.

If you're desperately short of time, or don't have the available free disk space, to let Bitcoin Core finish syncing... exporting private keys is an option as long as you take adequate steps to protect the private keys. ie. don't enter them onto websites, verify any downloaded wallet software (like Electrum) is legit etc.

Is it the privatekey that should be inserted with no need of the public key?
Isn't it dangerous to put in the private key like that?

 Hi yes there is option to import priv. key in Electrum. Just click the tab and add to electrum and it will show you the coins. Then you will have your bitcoin depending how much you had. Thanks. Share the love with all of us bud. Thank you.

Thank you both of you for replies!



Seems to be there.
Ok, but the right balance will come up eventually anyway?






Thank you very much for this reply!

When you say high risk to get the usb-stick infected, do you mean like 0,1% or 10%-90% ?
Its a new formated usb-stick btw.

Yes, we have been writing both the wallet-address and the private key down on a piece of paper.

If we would use the option "Import the private key straight from the initial Electrum setup", is that the same thing as if we would import the dat-file in another bitcoin core, or just adding the address and privatekey inside that program?
Its the same wallet just that we can open it from another app?

Enter a list of Bitcoin addresses (this will create a watching-only wallet), or a list of private keys.
Here we are writing the wallet-address, right? Like:
p2pkh:WALLET_ADDRESS

When do you add the privatekey? And will this be stored on the new computer anywhere? This option is like import the same wallet inside a new app? Nothing new is happening? This will also continue the sync?

Have you confirmed that "THE_ADDRESS_OF_THE_WALLET" actually still contains bitcoins?

If you go to a blockexplorer like:

https://blockstream.info/
https://btc.com
https://blockchair.com/bitcoin/
https://live.blockcypher.com/btc/
https://www.blockchain.com/explorer

And enter THE_ADDRESS_OF_THE_WALLET into the search bar (DO NOT USE THE PRIVATE KEY!!)... you will be able to check the current balance. Make sure that it actually contains coins before you bother exporting/importing private keys


Fully syncing Bitcoin Core with the wallet.dat will take longer and requires a fair amount of bandwidth (and possibly data storage if your node isn't in "pruning" mode)... but at least you can be assured that the balance at the end will be correct and it will show any and all coins for all the addresses in your wallet.dat.

Well, as long as you're moving the ".dat" file from one PC to another, I'd have to guess you're using an USB stick. That is a high risk: your USB stick or computer may be infected and the ".dat" file may move not only from one PC to another but also to some unknown malicious party's device. If I were you, I would just create a brand new wallet on the new PC and transfer the old balance to your new wallet.

Try to avoid moving files from one PC to another as USB sticks are a potential risk. Also, if you're using Bitcoin Core as your new wallet, I would personally wait for it to sync completely before sweeping the wallet - but I don't think there is any particular issue if you'd import it before the full sync, besides the fact that your wallet's balance will not be up-to-date. If you're using Electrum in light SPV mode, the synchronization takes literally a few seconds and it doesn't matter if you import/sweep it before/after the sync.

Edit: also, try to write the private key on a piece of paper and never store it on online storage or text files. Move your private key around as least often as you can. Google Drive, Gmail or ProtonMail are not safe ways to store your key. I usually write it down on a piece of paper multiple times, verify one of the lines I've written character by character to make sure I wrote the right thing and then just get rid of the electronically-saved one. I feel much safer having a piece of paper with a privkey on it than a Notepad file.

To import the private key into your new wallet,

• If you're using Electrum, you can either:
  
  • Create a new seed and sweep the private key (Wallet -> Private keys -> Sweep) into one of your new seed's addresses
  • Import the private key straight from the initial Electrum setup (choose "Import Bitcoin addresses or private keys" instead of Standard wallet) and then transfer the funds wherever you'd like
• If you're still using Bitcoin Core as your new PC's wallet: unlock the new wallet (if you've encrypted it) through the "walletpassphrase" command, followed by the "importprivkey" one. Here's the two commands you need:

Ok!

We got the privatekey after using dumpprivkey THE_ADRESS_OF_THE_WALLET
So now we have the address of the wallet and the privatekey (I guess?), is that the only thing we need?

What would you say would be the best option now, import the dat.fil to a new pc and continue the sync from there first and then send the whole thing to a secure wallet of any kind or directly swipe it to a new wallet without continue the sync-process first? Because that it possible, right?

Any dangerous high-risks we should avoid?

If the error you're getting is what hosseinimr93 has said (quote below),
Then there should be no passphrase set because you'll get Error: Please enter the wallet passphrase with walletpassphrase first. (code -13)
with dumpprivkey whether the address is correct or not.

Are you sure that you are in the debug console when using this command? Or you might be using Bitcoin-CLI?

Can you try to add a double quote in your address as a sample command below.


Make sure no extra spaces.

Hmm, oh, the passphrase might be the big problem. The thing is that he, the ones this is all about, don't remember if he even had a passphrase. However, he know that he don't remember it. But since the application is synchronizing it means that no passphrase should be needed, right? Really hope so, otherwise I guess its hopeless?





Oh, I will get back about that! I don't remember what it said. Will continue tomorrow.



Thank you for your help so far!

Do you mean "Invalid Bitcoin address (code -5)"?
If so, what you entered is not a valid bitcoin address.
That may be an altcoin's address. If that's a bitcoin address, it must start with 1, 3 or bc1. Otherwise, it's not a bitcoin address.

You probably only need the private key, everything else can be derived from that.


Either will work. Bitcoin Core isn't super resource intensive unless you want to synchronize it.
As long as your wallet.dat is backed up, you won't lose your coins. Make sure you know the passphrase as well.

Yes it is.

First, thank you for answers.
Is it correct that all we need is the address of the wallet and a private key? No more keys than that are necessary to import it in a new online wallet?








We tried to use dumpprivkey THE_ADRESS_OF_THE_WALLET but got the "invalid code-5" as a response. Maybe we did something wrong?










So I should install it on the old computer? It´s very unupdated I think. Or is it good enough to install in on a modern day computer and import the dat-file from an USB?

If I copy it to a new computer its nothing that will kind of throw me out or something from the old computers? (I mean the wallet is open now, don't want to suddenly be outside).

And, "1ADDRESS" is that the adress of the wallet?

Use this:

Your wallet has to be unlocked.


To import it into another wallet (e.g. electrum), make sure to use the corresponding prefix when entering your private key, depending on the address:
If the address starts with 1..: p2pkh:XXXX
If the address starts with 3..: p2wpkh-p2sh:XXXX
If the address starts with bc1..: p2wpkh:XXXX



Edit: Seems ranochigo was faster  

Yes. You can extract the keys out of the client, caveat being that you'll have to be sure of the addresses that contains the coins.

Firstly, go make sure you get a backup of your wallet.dat and keep it safe, do not share with anyone.

Download the latest version of Bitcoin Core (optional and it should work with older versions as well), install it and run the client. If you're sure of the addresses that contains the coins, then follow the steps below:
1. Go to Window>Console.
2. Key in the command if you have password protected your wallet.dat. Otherwise, go to step 3.
3. Key in the following, replace the address accordingly:
4. You should get a WIF private key, keep it safe first and export all the necessary addresses.

Download Electrum, validate it using PGP and it's signature and you can create a wallet to import the addresses.

Hello!

I got a question. Is it possible to find the private key and the things that needed to import an old wallet stored on an old computer? This wallet.dat-file is open in the application on the computer and the app is Bitcoin QT. Since the wallet is unsynced with the network is trying to complete the sync, but extremely slow, the wallet must be open, right?
I mean it should be possible to get to know the private key somehow?

The only thing we know is the wallets address.
We have been trying to use some commands in console with the wallet address input:ed but only get error "-32601" and "-5". Guess we need to put something other than the wallets adress in there?

What should we looking for, or is there nothing more to do?