Importing private keys creates different address

How does importing private keys work?

I have previously imported the private key for a 1Archive... address into Bitcoin Core and noted then it added an address like 1AXbRq... and I didn't follow it up further.

Today I have exported the private key for a 3... address from Bitcoin Core and imported it in Electrum. Electrum adds a 1... address and doesn't see any of the transactions.

How does this work? I understand that there is an underlying 1... address behind a SegWit address but how would I spend any BTC if it is not showing in my wallet balance? What else should I do?

If there is an answered question for this already on Bitcoin.SE I could not find it.

My private key begins with L.

Willtech

Posted 2018-03-24T10:01:01.723

Reputation: 2 657

Was the address that started with 3 a P2WPKH address? If so, that might help: https://bitcoin.stackexchange.com/q/72899/38618

– MCCCS – 2018-03-24T10:07:06.147

@MCCCS Okay, that's actually close. I have a 3... address not a bc1... address. I have hope it is going to be easily solvable. – Willtech – 2018-03-24T10:25:41.760

@MCCCS Actually, tried that method, Electrum says that the key cannot be imported. My priv key starts with L. – Willtech – 2018-03-24T10:29:45.250

It's completly irrelevant that your private key start with "L". Don't share it! – ndsvw – 2018-03-24T14:44:30.020

ICIN, the official download for Electrum is from https://bitcoin.org/en/wallets/desktop/windows/electrum/

– Willtech – 2018-03-29T13:02:39.493

Answers

I suspect you can import it directly from the console within Electrum (based on this PR). Currently, Electrum does now allow importing individual p2wpk inside p2sh addresses (the 3 segwit addresses). You can, however, still import an entire seed by using a BIP49 derivation path.

Try running the following in the electrum console:

key = 'your_key'
txin_type, secret, compressed = bitcoin.deserialize_privkey(key)
wif2 = bitcoin.serialize_privkey(secret, compressed, 'p2wpkh-p2sh')
print(wif2)

Then import the wif2 which it prints out

Raghav Sood

Posted 2018-03-24T10:01:01.723

Reputation: 10 897

That works. It imports the correct address. – Willtech – 2018-03-24T11:21:07.643

Good to know! I wasn't super sure, and currently away from a machine with electrum on it. Thank you for confirming. – Raghav Sood – 2018-03-24T11:23:04.143

Note since 3.1 you can just prepend "p2wpkh-p2sh:" to the private key before importing it. – Abdussamad – 2018-03-25T06:17:12.690

Prepend "p2wpkh-p2sh:" to the private key before importing it into Electrum. For example:

p2wpkh-p2sh:5Kkzs8XrJNAmf9VQDFeGBfaRvSByAvPK6DbDXw5BVqswWaXSG2Y

Abdussamad

Posted 2018-03-24T10:01:01.723

Reputation: 1 850

I cannot confirm this - I tried it on my priv key and I get an error but, then again I have already imported it. – Willtech – 2018-03-25T07:24:51.983

@Willtech it only works with 3.1 and above.

– Abdussamad – 2018-03-25T07:36:08.047

Just checked my version, it is indeed not 3.1 and above. – Willtech – 2018-03-25T07:39:59.040

you made me cry, after 6 hours of searching and trying. I wish I could give you +100 upvotes. Thank you. – Ashkan – 2018-05-08T02:40:46.393

-1

"I have previously imported the private key for a 1Archive... address into Bitcoin Core and noted then it added an address like 1AXbRq... and I didn't follow it up further."

First of all, I won't be answering the first question. It just sounds weird, and 99% it's caused by a mistake.

How does this work? I understand that there is an underlying 1... address behind a SegWit address but how would I spend any BTC if it is not showing in my wallet balance? What else should I do?

Here's how importing a P2PKH address works:

WIF result is affected by three parameters: Privkey type (a byte for BTC private keys), the private key (that also contains which y coordinate the pubkey has, if we want the compressed pubkey), and an extra 0x01 byte if we want the compressed pubkey. There's only one public key that can be generated using that WIF.

Here's how importing a P2SH address works:

1) Dump the WIF of the P2SH address

2) Import the WIF

3) Make a transaction, and watch how your wallet or Bitcoin Core doesn't recognize the transaction.

It won't recognize the transaction, because there's infinite number of P2SH addresses one can create using the WIF (Note: script has a size limit, so it's not infinite)!

To inform your wallet about your P2SH address, you should also import the script. And, this is not supported by 99.9% of the wallets. (However, the wallets can import Witness addresses, as they're standardized and widely used) That's why Electrum doesn't see your P2WPKH address, if you don't tell it to use the Witness address.

MCCCS

Posted 2018-03-24T10:01:01.723

Reputation: 5 827

p2wpkh-p2sh scripts are standardized in the bip. As long as you prepend "p2wpkh-p2sh:" to the WIF Electrum will recognize it as such in Electrum 3.1 or newer. In the case of 3.0.x you have to convert the WIF which you can do using the script @RaghavSood posted or this menu based one here.

– Abdussamad – 2018-03-25T08:31:58.733