Importing private key back-up into Bitcoin-QT

[clochard]

Hey guys,

I am technically a bit a Bitcoin noob, so I hope you guys can help me.

I have some back-ups on usb's (wallet.dat file) of an old Bitcoin QT wallet of a pc that is not working/starting anymore.

I have another computer now, I downloaded the Bitcoin-QT wallet, removed the wallet.dat that belonged to that new Bitcoin-QT from the folder where it was stored, imported the backed-up wallet.dat file, opened in the same folder a command window and typed: "bitcoin-qt.exe -rescan". Btw, When I made the back-up I changed the name of the wallet.dat file in another name, imagine it being called 'wolverine.dat'.

Bitcoin client started rescanning all the blocks and is now still 20 weeks away from being synchronized (it takes a shitload of time).

Have I done everything correctly? And when it finished rescanning, will my old bitcoin balance of the other wallet that was in the other pc appear? Until now my balance is 0.

Btw, one thing you should know is that the wallet on the other pc was encrypted. I am not sure if this will give any problems?

It would be great if some of you guys could clarify this for me.

Thanks in advance!

Best,

Clochard

[1713992524]

1713992524

[Light]

Pretty sure you shouldn't have any problems if you've done exactly as you've posted. You just need to wait patiently for the client to sync. Your encryption shouldn't give you any problems as long as you remember the password. If your impatient (like I am occasionally) you could download pywallet and have a play around it on an offline comp to see if you can extract the private keys. From there you could import them into a lightweight client (which doesn't need to download the whole chain) to ensure you have your balance. Or you could just wait...

[clochard]

Thanks for the reply! It is really appreciated

I do remember the password and I have it written down. Will it ask for the password ones it is synchronized?

I am wondering about this, because I also ecnrypted this wallet with another password (which I also remember and wrote down).

Best,

Clochard

[Light]

IIRC, you will be asked for your password when you try to do things that have serious ramifications (ie sending a new tx or trying to change your old password). Until then it'll simply watch for any incoming transactions and reflect that in your balance. It's been a while since I've used Qt so if anyone could confirm that would be nice.

[DannyHamilton]

When I made the back-up I changed the name of the wallet.dat file in another name, imagine it being called 'wolverine.dat'.

When you imported it, you changed the name back to "wallet.dat", right?

It has to be named exactly "wallet.dat".  If you left it named "wolverine.dat", or changed the name to "Wallet.dat", or "wallet.dat.dat", or "wallet", or "wallet.txt", or "wallet.dat.txt" or "wallet.txt.dat", then you'll need to re-do the -rescan.

I've seen other people accidentally rename the file in any of these ways in the past.

[clochard]

Oooh fuck, no    I did not change it back into wallet.dat

I was not aware that this was necessary.

Right now I do not feel like rescanning the entire blockchain. Do you guys think it is safe if I import the wallet.dat file to my wallet on blockchain.info? and how do I import the wallet.dat file into blockchain.info. Honestly I do not see the option?

From there I would like to transfer it to my electrum wallet. I am just wondering if I trust an online service with a reasonable sum of bitcoins.

Feedback appreciated

Best,

Clochard

[DannyHamilton]

Oooh fuck, no    I did not change it back into wallet.dat

I was not aware that this was necessary.

Right now I do not feel like rescanning the entire blockchain. Do you guys think it is safe if I import the wallet.dat file to my wallet on blockchain.info? and how do I import the wallet.dat file into blockchain.info. Honestly I do not see the option?

From there I would like to transfer it to my electrum wallet. I am just wondering if I trust an online service with a reasonable sum of bitcoins.

Feedback appreciated

Best,

Clochard

If you decide you trust blockchain.info, here's the import page:
https://blockchain.info/wallet/import-wallet

[clochard]

Yes I have seen that link as well. Problem is, it says: 'create a new wallet'.

I don't want to create a new wallet, I already have one on blockchain.info

I cannot find the option to import the wallet.dat file to my existing wallet. Or is that impossible?

[Light]

Right now I do not feel like rescanning the entire blockchain. Do you guys think it is safe if I import the wallet.dat file to my wallet on blockchain.info? and how do I import the wallet.dat file into blockchain.info. Honestly I do not see the option?

From there I would like to transfer it to my electrum wallet. I am just wondering if I trust an online service with a reasonable sum of bitcoins.

Feedback appreciated

Best,

Clochard

So far Blockchain has been fine (although its inadvisable for long term storage) so if you were worried, you should be fine for a quick import and subsequent transaction. Just make sure that you triple check the address you're sending your coins to is the one in your Electrum wallet - it's happened to countless people in the past.

Alternatively if you don't trust Blockchain, then you could follow the route I specified in my earlier post with pywallet. Just remember to decrypt the wallet as part of the command (specified below - don't recall if it was in the README).

Code:

--passphrase=PASSPHRASE 

If you need anymore help, I should be around tomorrow - meanwhile I'll leave in you in Danny's more than capable hands.

[Foxpup]

Why is everybody making this more complicated than it needs to be?

If you decide you trust blockchain.info, here's the import page:
https://blockchain.info/wallet/import-wallet

This not necessary, because neither was the rescan. Close Bitcoin-Qt if it's still running (and be sure to wait for it to fully shut down), delete (or rename, if you're paranoid) the empty wallet.dat created by Bitcoin-Qt when you first attempted to start it, rename wolverine.dat back to wallet.dat, and restart Bitcoin-Qt. Your balance should be displayed immediately; there is normally absolutely no need for a rescan when restoring a wallet backup.

[clochard]

When I do that, it opens again and continues scanning. Still 15 weeks behind

[DannyHamilton]

there is normally absolutely no need for a rescan when restoring a wallet backup.

Really?

Odd.  I thought a rescan was often necessary after restoring a backup.  I'll have to search through threads and see if I can find evidence of that.

EDIT:
Ok, I suspect that the reason I thought a -rescan might be necessary was because I had previously read some of these posts (and others like them):

- snip -
Place the November 7th backup in place and try the rescan.

just replace the wallet.dat file in the bitcoin folder with the backed up version, then use -rescan

Yes, a rescan has solved the problem.
- snip -

just copy back and spend

might be good idea to start the bitcoin client with the -rescan switch
- snip -

Do a rescan.
Start it from the command line with the -rescan option.
Also, make sure you have your most recent wallet.dat on the data folder.

- snip -
Restoring of a wallet backup is supported since 0.3.20 with -rescan
- snip -

You can simply rename the wallet.dat on your current Bitcoin installation, and temporarily put a copy of this old backup wallet.dat there. When you launch bitcoin with the -rescan option, it will update the wallet to show the correct balance.
- snip -

- snip -
the client can become confused when you start switching keyrings back and forth is not a problem - just run -rescan.

- snip -
Whenever you copied your wallet from backup place, you should start bitcoin-qt with rescan option:
- snip -

- snip -
So assuming that you using the backup of the encrypted wallet and that no errors are occurring you might need to run bitcoin with the -rescan option.

- snip -
So the old backup could still have some or all of the coins yet.

Of course, the encrypted wallet should not be missing anything, so like CIYAM suggested,  -rescan
- snip -

[clochard]

Okay, another question then.

I currently changed the name back to wallet.dat

If I continue scanning the blocks (15 weeks behind), will the bitcoins appear on my balance after completing the scan, or should I have changed the name of the file before doing the entire rescan?

Because simply closing Bitcoin client and restarting it (with the name changed to wallet.dat), does not give me my balance.

Thanks!

Clochard

[DannyHamilton]

If I continue scanning the blocks (15 weeks behind), will the bitcoins appear on my balance after completing the scan, or should I have changed the name of the file before doing the entire rescan?

Because simply closing Bitcoin client and restarting it (with the name changed to wallet.dat), does not give me my balance.

The wallet will not display any balance until it finds the block transactions where you first started receiving bitcoins with this wallet.  It will not show the correct balance until it has finds the last (most recent) block transaction where you received or spent bitcoins from this wallet.

[clochard]

But this wallet is new, I just downloaded it a few days ago on a new pc.

So in other words, it will not show my bitcoins?

How do I get them in this wallet in that case?

[turvarya]

But this wallet is new, I just downloaded it a few days ago on a new pc.

So in other words, it will not show my bitcoins?

How do I get them in this wallet in that case?

I think, you misunderstood something.
Sure, your bitcoin will Show in your wallet, when you have imported your wallet.dat right and when it has downloaded/scanned the last block.

[clochard]

Allright, I guess I will just wait until it is finished scanning. If the bitcoins don't appear, I will let you guys know.

Thanks for all the help till now

Best,

Clochard

[Foxpup]

When I do that, it opens again and continues scanning. Still 15 weeks behind

Clarify: does it say it's "rescanning", or "synchronising"? It can't continue scanning if you swapped the wallet files. It can only resume a rescan if it's still using the same wallet file. And if it's synchronising, a rescan is not useful anyway.

Odd.  I thought a rescan was often necessary after restoring a backup.  I'll have to search through threads and see if I can find evidence of that.

The wallet.dat file stores the height of the most recent block, and blocks beyond that (if any) are automatically scanned for new transactions on startup. A full rescan is normally unnecessary and pointless.

Because simply closing Bitcoin client and restarting it (with the name changed to wallet.dat), does not give me my balance.

That's damned unusual. Are you sure you renamed the file correctly? How large is the wallet.dat file?

Sure, your bitcoin will Show in your wallet, when you have imported your wallet.dat right and when it has downloaded/scanned the last block.

The last part is incorrect. It is not necessary to even have any blocks at all for your balance to be displayed (though it will be displayed as "unconfirmed" in that case).

[clochard]

Well, I renamed it to 'wallet.dat'

The file itself is 72kb of size.

p.s. I meant synchronizing.

[Foxpup]

The file itself is 72kb of size.

So, it didn't actually contain any transactions at the time you made the backup? That explains a few things... Nothing to do but wait until it finishes synchronising and (hopefully) your transactions will start appearing one by one. If not... didn't you say you have multiple backups? You really ought to be trying the most recent (or largest) file first.