Bitcoin Forum

edit; lost a btc wallet, then recovered it using awesome recovery software from makomk:
https://bitcointalk.org/index.php?topic=25091.msg344382#msg344382

no worries. Just use the backup you already made before you moved around your wallets and started deleting stuff then let it confirm the blockchain again overnight.

I guess, he forgot about the backup part ...

Very likely. Sorry to hear that, hope you didn't burn too many Bitoins. But it's kind of like having paper-cash, moving it around different wallets and then throwing one of those wallets into fire.

The difference is that physical wallets are really hard to back up (I'm not aware of any technology that successfully does this). Digital wallets are really easy to back up. One just has to think of it.

That said ... it will be great once the Bitcoin client has some mechanisms for backups / encryption built in.

So you basically deleted your own wallet. Nice one.

So, what you basically did is this:

You have Wallet A and Wallet B (think of physical wallets). Wallet B is a new wallet you just bought. It's empty. Then you take some dollar notes from Wallet A (which is full of dollar notes) and put it to Wallet B ("the address I sent the BTC to" = "Wallet B"). So the dollar notes were in Wallet B. Then you took Wallet B and burnt it to ashes.

If you had a backup of Wallet B (done magically with some molecule duplication technology), you'd have Wallet B1 and B2, both providing access to the Bitcoins you sent to Wallet B. Then when you burn B1, it's not a big deal - you still got B2.

In any case: Since you took the Bitcoins / dollar notes out of Wallet A, they're no longer there. So, if you completely emptied Wallet A, you could safely delete / burn Wallet A (however, if anyone ever sends you BTC to an address from Wallet A, those will be lost forever because no one can send them anywhere anymore).

Have you got a hard disk or a SSD/FlashHDD?

I'm afraid that answers some of the suggestions:


If you had just "deleted" it, it would be kind of like putting it into a really huge, ugly, dirty trashcan. In that case, you could dig into that trashcan and maybe recover it. But my understanding is that you've literally burned it.

Maybe he could dump / freeze the ram? Is it possible to copy the swap-file (maybe with a live-cd)?

Well, I was hoping it was already given... I assumed that you already made a backup encrypted copy of your original wallet you started with before you began testing anything. If you didn't then you are shit out of luck I'm afraid.

You say it is an unconfirmed transaction?  Well, I would shutdown Bitcoin.  Make a copy of you wallet!  Restore a copy (you do have one right?).  Then restart bitcoin with -rescan.  Your coins might not have been sent yet.  It happened to me.  The network fouled up and so my transaction was effectively canceled.  Not that I wanted it to be, but in your case you can always hope.

And check block explorer to see if your deleted account got the coins.

Why burn an unused wallet, anyway?

Please please please people - DON'T do this sort of thing with "real" coins.

There's a testnet in a box that will allow you to play in a sandbox all you want:
http://sourceforge.net/projects/bitcoin/files/Bitcoin/testnet-in-a-box/

There but for the grace...   I've only managed to make boneheaded market moves so far.

After you send bitcoins to a public key (a "receiving address") and the transaction is confirmed into the block chain, the only way those bitcoins can be spent is with the corresponding private key.

Unless you can recover that private key from a copy in disk or RAM, the BTC cannot ever be spent.

In theory, if you could quickly grab the majority of the network's hashing power, you could perhaps rewrite the block chain to remove your original send, in which case the coins would be available to you again. But realistically this cannot be done without control of the largest mining pools. As 40 minutes or more has passed already, even that window is closing now.

Sorry to hear about your loss.

I just saw your post from 7th December 2010 (http://jonathanriley.net/index.htm#y2010_m12_d07_01) which ended with the words "Where ever will this lead?".

Ouch.

I'm sorry to hear about your loss. I hope you did not lose a large amount, and that you can quickly recover the funds.

You never know, in 100,000 years time, someone might generate a collision and send you your coins back.

just out of curiosity, as long as there are no confirmations, what exactly would happen if the client would have an 'undo' button that generates a double-spend to myself? would both transactions be invalid? if not, could the transaction to myself have a higher fee to motivate the miner to pick it over the other one?

Having read about multiple early adopters losing large amount of Bitcoins (messing up backups, malware, etc.), I wonder if humans in general can actually deal with this.

Is 100% vigilance possible at all times?

Please don't work with the PC! Use another pc to google!

Here is a "Cold Boot Attack Tool for Linux" to dump the ram. But this is very risky. Maybe there are a way to dump the ram without to turn off the pc.
http://www.linuxjournal.com/article/10289

RAM DUMP UNDER LINUX:

System memory dumps on Linux

http://www.theknotter.net/system-memory-dumps-on-linux/

Sorry about that. I did not look at the blockchain. I want to but it seems the site is down.

Use the local network to dump the system-memory!

http://www.theknotter.net/system-memory-dumps-on-linux/

Ouch!  It looks like you lost it all.

Lesson learned.

Personally I save ALLLLLLLL  Wallet files on a flash drive just in case.  It costs me nothing in effort, and in the case we have here, nothing in Bitcoins.

Are you sure you deleted it permanently? I don't know about this in too much detail, but sometimes when you delete a file the computer doesn't actually overwrite the bits on the hard drive. It just erases the pointer in the file system that says "wallet.dat starts at this hard drive sector, and is X sectors long" (over simplified, but enough for the purposes of this discussion).

Try to avoid doing anything that will write new data to your hard drive, so if possible avoid using the computer at all for now, and use a laptop for the following: Do a Google search for "how to recover deleted files" and/or "undelete files in Windows" (or whatever your OS is).

I think you will be able to find programs that will read your hard drive and allow you to recover "deleted" files. Second, if your wallet.dat was in a Dropbox folder, you can just get a backup of it from the DropBox web UI. One thing I do is create a small TrueCrypt volume and move my wallet.dat to that volume. Then I create a symbolic link (windows 7) from Users/Capitan/AppData/Roaming/Bitcoin/wallet.dat -> TrueCryptVolume:\wallet.dat. Then I unmount the TrueCrypt volume. The encrypted volume is stored in my DropBox, so even if someone hacks my DropBox account they would still just get an encrypted copy of my wallet. This also has the benefit of creating automatic version history of my encrypted wallet in case it ever gets deleted.

The only downside is that I have to mount the volume whenever I open the client, but I pretty much never have to do that unless I want to send bitcoins somewhere else. Theoretically I could keep the volume encrypted and unmounted for 20 years and log in 20 years from now, and the Bitcoin client will read the block chain to push all the Bitcoins I received during those 20 years into my wallet. I don't think I'm ever going to mount that volume in my current PC again, because I'm paranoid about security after recent posts on this board. I will have to set up a new secure and clean one on Linux and mount from there the next time I need to open the wallet.

Linux shred. He deleted it with extreme prejudice.

Ah, I miss
Ah, I must have skipped the part where he said that. Sucks to be him then.

365.18 btc .....dude.......ouch! ........WHY??....why did you do that???????
you could have tested sending these btc to my address....but noooo.....doh
next time, please use 1HfX1okdauFE5GxxtPa3ZMHmzZYNCt6j19 to waste some btc please :-/

365.18 btc ~ 5660.29USD (1btc = 15.5USD at mtgox)

i can feel your pain op

I never delete any wallet, not even empty/test wallets.

Having read about multiple early adopters losing large amount of paper currency (fires, bandits, etc.), I wonder if humans in general can actually deal with this.

Is 100% vigilance possible at all times?

In my opinion the chance of human error wiping out your entire wealth is much greater with Bitcoin. But of course you could mitigate that risk by storing it with trusted third parties.

A single wallet.dat is the point of failure. You're much more likely to, through human error lose all your wealth if you bury it in a chest in the back yard and then forget when you move.

I'm laughing at the pure stupidity of the OP right now.

WHY? WHY WOULD YOU USE SHRED?

Time to add it to the known lost bitcoins thread...

And? Have you dumped your system ram ?

Can't believe the recklessness of people and their wallet.dat files.  It blows me away.  I have less than he lost and I've got it double backed up and offline (not on any computer) unless I'm using it then promptly delete it after double backing it up again.

Remember this is like cash.

I've got an encrypted backup on a thumbdrive, just in case... probably not going to bother with more than that unless I get a lot more BTC than I have now.

we desperately need wallet management in bitcoin client.

Go for it! Patches are welcomed.

If you're not a coder, you could offer a bounty instead.

Linux shred does not work on file level. That's a prehistoric tool. Stop using the filesystem with the wallets on it immediately. Scan the whole partition for wallet-like patterns after that.

Guys, I totally messed up. I was hungry, and I didn't have any clean silverware. Taking what I thought to be an empty USB drive, I proceeded to spread peanut butter with it, and jelly (yum - strawberry!) on some bread. But then the dog started barking and totally distracted me. I turned around, and much to my dismay the dang beast leaped up and snatched my USB-knife out of my hands!

There he was, snarfing down my USB drive, when I realized... oh no... my WALLET WAS ON IT.

So, I tried to reach down his throat but it was no good. He didn't like me doing that, and clamped down pretty hard on my hand. I think I broke something too, because I heard a snap. Or maybe that was the USB key case cracking in my dogs throat, I'm not sure. So, I put things away while bleeding copiously everywhere, and sat down clutching a soaked dish-rag as a bandage to check on my wallet backups.

Well, wouldn't you know it, my dog had some kind of coughing fit and BAM, the key flew out of his mouth, into my eye!! Now I'm screaming a lot and the neighbors are starting to shout at me to knock it off, but I can only see out of one eye here - and goddamn does it sting! Stupid dog!

Now I realize I'm losing too much blood, and I think I might be close to shorting out my laptop. The dog is barking, the USB drive is lying somewhere in the room covered in dog drool and bile, perhaps unrecoverable, and my vision is starting to turn into a tunnel of blackness....

fjda4ebnjf.,bmnnnnnnnnnnnnnnnnnn

You should have encrypted and backed up your eye. Your fault. It's a free market, tough luck.

Almost as good as the Voldemort story... Which only wins because it's true.  :D

+1

• 'Empty' wallets might contain value lower than 0.01, eg 0.00154842 btc.
• 'Empty' wallets might contain value much higher than 0.01, if they are somehow corrupt and not reporting the correct balance.
• 'Empty' wallets might contain an address than has been made public (i.e. a donation address) that might receive unexpected funds one day.
• It's easy to move all your unused wallets to an encrypted archive instead. Mark them by the date they were archived or something.

Yeah, I read somewhere that shred doesn't even work on modern (journal-based?) filesystems such as ntfs and ext3. Writes are done on fresh blocks, leaving the original intact until some other write operation overwrites it. which is why you should stop using the disk immediately.

Your wallet should still be on the disk. Good luck finding it, though it is doable.

How appropriate that the BTC resurrection is celebrated with a thread resurrection.

The shred command is a lie? It doesn't obliterate data?

As far as I gather, if it ever ended up in the page file, or if there was ever a backup copy that wasn't shredded, then you can recover it.

One of the reasons I'm interested to see exactly how secure the client side wallet encryption for Bitcoin is going to be.

If you consider the chances of hardware failure, data corruption, user mistakes, and the fact that the wallet use to be hidden somewhere in the system partition (at least make a portable client, so you know where your wallet is!), I think they are biggest threats than viruses.

I did setup a redundant automatic encrypted backup of my wallets in the cloud (on several accounts on live and gmail space) using Cobian backup and Gladinet cloud desktop (both freeware) and I would recommend to anyone to do s.t. like that.

Congratulations! Slightly surprising that worked, but I guess shred really isn't an 100% reliable way of deleting files these days. Most of the warnings in the shred manpage refer to setups that aren't actually very common...