Topic: Lost Bitcoins in Bitcoin Core wallet - what now? (Read 368 times)

I assume this mempool.dat is the only thing left from your old wallet, make copy of the mempool.dat before trying this
If you want to try, on console type getrawmempool then check one by one by typing getrawtransaction txid
hopefully one of the rawtx is your unconfirmed transaction, and save this rawtx on text file or broadcast it

Then Samsung and Seagate would both be out of business.

It HAS had HD Wallet integration... assuming you created your wallet AFTER it was introduced and you have the "HD" icon in the bottom right corner, you have an HD wallet:



Not quite 100% accurate... an HD wallet can derive all it's private keys from a single "seed". The "seed" (like Bitcoin private keys) is just a really really REALLY big number. The 12/24 word seed mnemonic (aka seed phrase, aka wallet words, aka seed words etc) that you're thinking of is simply one way to represent this "seed" and is specified in BIP39 (https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki)

Bitcoin Core does NOT use BIP39 seed mnemonic phrases to backup the seed/wallet. And there is no (known?) way to extract the seed from a Bitcoin Core wallet. Instead, you are meant to take a backup of the wallet file itself. Any copy of the wallet file will enable you to generate all future addresses.

However, one very important thing to note is that Bitcoin Core actually CHANGES the (hidden) seed if you encrypt the file (by default, the wallet file isn't encrypted) or you change the encryption password... so one must remember to take a new backup every time the password is changed (or set for the first time).

OP may have been using an HD wallet (depends on how old their Bitcoin Core wallet is)... but yes, if they have not made a backup, that is a grave mistake.

Well, I never used bitcoin core's wallet to hold actually bitcoin.  I ran a full node for years, but with an empty wallet, because when I started with bitcoin, and I learned that core's wallet didn't have hierarchical deterministic keys (HD), I didn't want to use it for exactly the danger that you underwent.  I prefer electrum as a wallet, because that is, like almost all other wallets, and like almost all other *crypto*, using a HD key system.  But I'm surprised because I read that bitcoin core DID integrate such an HD system since June 2016.
An HD wallet can derive all its private keys from a single pass phrase, which is something you have to put on a piece of paper and put in your safe.  With that pass phrase, you can reconstruct all keys.  So even if your wallet file gets corrupted, you can always find them back.  Of course, you have to protect that piece of paper against theft !  But you do not depend on electronics to keep your coins.

With simple random wallets, each key is a random number, saved ONLY in the wallet file.  If that gets lost, you're done.  But of course, you were already in very great danger by not having a *back up*!  That's crazy.  You don't have a backup of your computer ?  The reason why simple wallets are problematic, is that between backups, you might use new addresses (new keys), which could get lost if the disk gets damaged, or the file gets damaged, between backups.  This is why I don't like them.  You have a backed-up wallet, you do a payment, it generates a new return address, you disk breaks down, and you've lost all your coins, because the backup was too old (namely 10 minutes before the payment).  With a HD wallet, that's no problem, from the pass phrase (in the wallet and on your piece of paper), it can find all keys again.

So, you're the victim of 2 simultaneous problems: not using a HD wallet, and not having made a backup.  The first thing is a technology problem, the second is simply crazy.  You never ask yourself: if 2 minutes from now, my disk is dead, what will I do  ?

Everything upto this point, all the steps you performed are correct.


You have made a serious blunder here. You should never remove wallet.dat ever, unless any unconfirmed transaction(s) goes through, or unless you have noted down the raw transaction seperately.


Your wallet will relay your pending transactions (if any) through peer nodes unless it's confirmed. By deleting wallet.dat, your wallet no longer is able to perform that.


No, it isn't. Don't blame your fault on the underlying technology which works excellent for everyone. Even Satoshi stated this (in verbatim):

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It's gone, unless you either remember the transaction ID or have saved the raw transaction details for reference.


Keeping the client open will help in subsequent re-broadcasts of your pending transactions, generally after every hour. In this case, I presume your transaction got flushed by the peer nodes and your client is unable to re-broadcast it.

You are now left with re-broadcasting the transaction manually.


Just because you screwed up doesn't imply the whole system "sucks". It never will.

Bitcoin protocol is quite the same as BitTorrent protocol. The only difference is that, on the Bitcoin network people value only coins that are "unspent" as marked by the "the most current and heaviest blockchain". The "spent" coins continue to exist, but nobody gives them any value, unlike that of BitTorrent network, where both the files in sender's and receiver's clients are still playable and valuable at the same time.

Nope. I only have the receiving address but that's proven useless.

I will be leaving the Bitcoin Core client on overnight to see if anything is stuck in the mempool.dat file but I highly doubt it. Looks like ~Satoshi didn't plan for large scale integration.

So I'm guessing you could not find the tx information.

If you still have your address, you could at least find out if it is still is stuck.

People worry about the online wallet, but it would helpful in this scenario.

It doesn't show on any of those. I literally closed the client and deleted the wallet.dat file the moment it said the coins were sent without any confirmations showing up. I thought the message that the coins were sent was enough, clearly this was not the case and Bitcoin being as old as it is, just makes you wonder why the client is so shit after all these years. As if no one really cares for real world application and instead everyone was just using the network as an investment place.

I just finished with a deep scan and it did not find anything. IMO most of you think technology is better than it actually is.

I will give it a few days but if my understanding of how the bitcoin technology actually works is correct then the coins are lost and the technology isn't as great as some of you may think it is. If those coins don't come through the simple answer would be that the Bitcoin network has blind spots which centralize the network as to avoid them you need to be well connected with other peers.

plug in that destination address on this block explorer bitaps.com or btc.com
if it was broadcasted successfully and reached one of these nodes, you will be able to see the unconfirmed tx
bitaps will keep track of it even if other nodes and the whole network has dropped it completely

IMO this whole thing defies common sense.  If you delete the wallet it should be easily recoverable period.  You must have waited way to long to try and recover it.  Still should be able to find it regardless.

I tried using Recuva as well as a few others and nothing. After deleting the wallet.dat file I reopened Bitcoin Core which created a new wallet.dat file. Maybe this new one overwrote the old one? I'm dumbfounded myself as I thought these recovery tools were much more useful although this doesn't quite seem to be the case.

The Bitcoin files are on another drive and not on my C: drive. I thought this would make it even easier to recover but this was not the case. I am currently doing a deep scan with another tool and there's a few more hours left. We will see what if anything this brings us.

I like this analogy, makes perfect sense.

Thanks for your help.

I thought that bitcoin core had HD wallet integration since June 2016...

Nope, nothing like that. It just worked at launch. It had a default address and then I created a few new ones.

May i ask why you weren't able to find your wallet.dat file?
If you weren't writing hundreds of GB's of data onto your HD after deleting your file (today ?) it should be easily recoverable.

The only reliable way to gain access to your coins is to recover the file.
Which software did you use to search for your file?

It is important to NOT use that disk anymore and make an 1:1 image (e.g. DD-like, https://en.wikipedia.org/wiki/Dd_(Unix)).
Then use any recovery software you wish to search for your wallet.dat.. The chances are very high of getting your file back.
The more you are using your hard drive the lower your chance will be of recovering the file.

Well I think since you're using low fees you're waiting for your transaction to be confirmed right? It's not lost. try checking out on the address that you sent the funds to check it on Blockchain.info and you can see where is the funds heading to if you did send it or not.

That doesn't matter.

This is not how Bitcoin Core works.

But when you set up your wallet, didn't you have to copy a pass phrase on paper ?

I've tried using multiple recovery tools and I am unable to recover the wallet.dat file.

More importantly I shuffled the coins around 2 different addresses within the wallet prior to sending them out.

I can understand that deleting the wallet.dat file was a mistake but once the coins are sent into the network IMO in a good technology scenario they should always reach the destination just like a bank transfer otherwise it isn't practical in real time value and the whole bitcoin thing is just a bubble waiting to burst. Technically I put my coins in a black hole by deleting the wallet, even though I sent them out before doing so.

I have the original mempool.dat file. Would I be able to find anything related to the transactions in this? I have the destination address but from what I can see this isn't of much use as blockchain.info doesn't show anything.

Thanks guys.