This seems like a DNS error.

Currently there is a DNSSEC root key rollover. Today is the day where the old root key is being invalidated.
The new one is already active for months.

Do you run your own DNS server ? If so, you have to do this mannually.
If you are using a DNS server inside of your network, contact the administrator.
And if you are using the DNS server of your provider, they didn't change it yet. In this case, switch to googles: 8.8.8.8 or 4.4.4.4.


This might be not the reason, but would be very plausible. Does anything else work as expected ?
Try to visit a site you never visited before (to make sure DNS works - and IP address it not taken from DNS cache).

This is 100% scam.

And it even isn't a new scam tactic. People get messaged to 'help' recovering funds on an completely unknown exchange/gambling site/whatever.
The scammer first is going to 'transfer' you some 'bitcoins' on the site (which do not exist because it is a scam site run by the scammer).
Then if you want to withdraw them, you first have to deposit a  ****fee (e.g. 'verification fee'). And that's what the scammer wants to achieve. He wants to trick you into paying this fee.

Do not fall for such tactics. It doesn't make sense to deposit something into a site to be able to withdraw (an exchange would simply deduct the 'fee' from the amount available).

Start with the basic information and explain your issue detailed. Please answer these questions:


- What address should have received what amount of BTC ?

- Did you get a transaction ID when withdrawing your coins ?

- Did you check your address on a block explorer ? Does it show a transaction ?

This all depends on the definition of crypto..

For me, a cryptocurrency has to rely on public key cryptography. The exact variables (PoW/PoS/.., inflationary/deflationary, max supply, etc..) don't matter.

A governmental issued cryptocurrency would just be e-fiat. But if (for example) it is a fork of bitcoin with adjusted parameters and additional stuff, it still would be a cryptocurrency.
Ripple's foundation can inject 2 times the whole current circulating supply into the eco system. This is 0 decentralized and one entity has full control, but it still is a cryptocurrency (even if it's not a really good one). At least in my eyes.

The security comes through the big amount of possible seeds. Adding one additional word/phrase wouldn't change too much.

The main reason is the possibility to create another 'wallet' based off the same seed.

That's especially interesting because it allows you to add plausible deniability (standard seed -> 'fake' account with small amount; seed with extension -> your real wallet holding your full amount of coins).
In case of being forced to give the seed away, you only will reveal the 'fake' wallet.

Actually bitcoin is extremely small (almost negligibly small) compared to the banking sector.
They are not concerned. At least not yet. The moment definitely will come. But currently bitcoin just seems to be some random internet money.




Bitcoin is by far not anonymous. It is pseudonymous, but not anonymous.
All information (sending-/receiving- alias, amount, time) are stored inside of the blockchain, forever.

If you can link an address to a person, you have full overview over his transactions. This would not be the case if BTC was truly anonymous.

A good place to get started is https://bitcoin.org/en/. Scroll through the wallet section and choose the most suitable.
The two most frequently used and suggested wallets are (1) Core (full node - needs you to download, verify and store the whole blockchain (~180gb)) and (2) Electrum (lightweight client - receives necessary information via online server).

Regarding buying bitcoins, usually you don't send cash via mail.. no. This sounds shady.
Depending on your country, there are multiple exchange to choose from. I'd suggest using the 'bigger' and 'more used' ones. They tend to be more secured (not guaranteed!).
It is important to not store your coins longer on an exchange as necessary.

If you have 256gb, you don't need any pruning at all. The best in this case would be to store the complete blockchain.

Also, note that this might not work out as you are expecting. Core needs a continuous connection to the memory. This might fail with a SD card.
In this case some data is going to be corrupted, requiring a resync.

But in theory.. yes, this would be a 'light wallet' (in terms of portability) using a full node.

If a UTXO is unspent it means it is ready to be spent (not spent yet -> unspent).

Check your address (which should have received the funds) in a block explorer (e.g. blockchain.com).
Enter your address at the top and look if there are any incoming transactions.

What wallet are you using ?

Also, it seems like your xpub is invalid. There is no reason for you to post it publicly. Anyone will be able to derive all addresses ever used by your seed, destroying your whole privacy.

I don't exactly understand what you want from us..

If the inputs are the senders priv key, address, change address and receivers address, simply call the function with all of these parameters.

For examples (code snippets), look at github (e.g. https://github.com/bcoin-org/bcoin/blob/master/docs/Examples/create-sign-tx.js).

This link is just a payment request to your address. It is a way to set the address and amount for someone to pay for.
Your address did not receive any coins yet. Your electrum client has nothing to show.

You can check your address on a block explorer (e.g. blockchain.com: https://www.blockchain.com/btc/address/1BnVUuBXAAseSz9uKcgt9dEgzHTjkFXyUF).
If there were a transaction, the site would show it.

This is the general flow of such an action, except for the stored hash of the private key (that's not necessary at all and non-usable).

The devil is in the detail. How do you generate a new address, how do you store the private key, where do you map it to the customer ?
How do you keep the private keys secure enough so that nobody can access it ?
How exactly does the 'background process' work ? Is it safe against each kind of manipulation or could an attacker simply simulate a payment ?

There is a lot to consider when building such a system.


People who want to have software which handles payments coded for a cheap price, will receive low quality work. And this will cost you way more in the end.
The proper way is to either get some good developer to build the system properly themselves (with security in mind) or to review/audit and setting up an open-source server.

Pruned mode is for people who want an up-to-date client who has validated the whole chain itself but don't want to let the blockchain occupy too much of your hard drive.

It all depends on what you want to achieve with your node. If you just want to use it as a safe wallet, set the prune limit to as much as you want core to have of your hard drive.

However, if you regularly swap wallets inside of core you'll need to download the whole blockchain again to build the available UTXO's.
If you have enough disk space (HDs are extremely cheap currently), it is better to run core without pruning. In case of any failure, you will save yourself from downloading the data again.

You are free to use whatever you want.
A 2FA wallet is a multisig wallet with 2 out of 3 signatures required.

The process is like this:
- Your wallet generates 2 out of 3 private keys, TrustedCoin creates the 3rd key.
- Your seed will be your backup for those 2 private keys.
- Your wallet deletes one private key, so that it holds only 1 key now

When you want to transact, you are signing your transaction with your 1 private key and after verifying 2FA through GA or whatever, TrustedCoin co-signs your transactions making it valid.

Obviously this is more secure than simply holding all private keys on an online computer. However i would never regard this being anywhere as secure as an offline setup.


If you are looking for a good tradeoff between security and convenience, you might want to get a hardware wallet.
Those can be plugged in to online and/or infected computers, while always keeping the private keys in a secure environment not leaking anything.


Back to your question, you can do this. It is safer than a 'normal' desktop or mobile wallet. However it is by far not as safe as an offline setup or a hardware wallet.





That would probably be the easiest way to move your coins to a new (true) offline-setup.

Let me rephrase this:

It is just that the only way to access the key is by being in range of a meter for less than a second.


IMO offline storage should be truly offline. No communication. No internet, WLAN, LAN, Bluetooth and also no NFC.
Either choose an old computer to achieve that or a paper wallet. There are no other ways i am aware of to achieve a (relatively convenient and still secure) cold storage.

I am assuming you want to build something on top of that (at least that's the most obvious reason for forking the code and running it yourself).

So you will have to read and understand the code anyway. Finding and changing a variable seems to be a solid first step.
I'd suggest to simply modify the code according to your requirements.

If you have a clue what your password might be or know some specific characteristics of your password you might try out btcrecover.
But you need a pretty decent clue on what it might be.

For example, can you limit the amount of characters it had (e.g. 6 to 8 ) ?
Can you tell for sure which symbols you have (or have not) used ?
Do you regularly use any specific sequence (e.g. always 123 at the end) ?

All of these things are helping to decrease the search space. If you can guess it good enough, you can bruteforce it.

Are you concerned about your local storage or the data it needs to transmit via your network ?

Pruning limits the space core will take on your hard drive. But all blocks still have to be downloaded and verified by your node.
Core just won't keep more blocks (in Mb) than set when using prune=N.

From their site:


So first make sure you are connected to at least one of these nodes.

Afterwards you can use the serach bar at the upper right to find your node either using your public key or IP address.

Yes, this caused your issue.

You need to either create a 'standard' wallet (it doesn't matter whether legacy (addresses starting with 1..), nested segwit (p2sh, starting with 3..) or bech32 (native segwit, starting with bc1..),
or create a multisignature wallet (address starting with 3..).

Your 2FA wallet is a multisig wallet, but needs an online connection to the 2FA-service-provider (TrustedCoin) since you are not holding the necessary amounts of keys inside of it.
The 2FA isn't necessary anyways if your keys are hold on the offline machine.

If you don't need a multisig wallet, but only want a 'normal' cold wallet just create a standard wallet without 2FA / multisig on your offline machine.
Then click on 'Wallet' -> 'Information' and import the shown master public key (starting with xpub.. ) into your electrum on the online machine (File -> New -> Standard Wallet -> Use a master key -> Enter your xpub..).