Bitcoin Forum

I haven't synced my Bitcoin wallet in over a year, if I send bitcoins from it, do I have to wait for the blockchain to finish downloading for the coins to be sent? I'm using Bitcoin Core v0.9.3.0-g40d2041-beta (64-bit)

better wait to blockchain download .... your bitcoins could be already gone, stolen  :)

to speed things up you can import private key to any lightweight (microwallet, electrum..) or web wallet (blokchain.info) .. this should take only few minutes

Waiting for the sync to complete is the only way to know for certain exactly how many bitcoins (and which bitcoins) you have available to send.  As Wusolini pointed out, if you don't wait for the sync to complete, you could end up accidentally trying to create a transaction with bitcoins that you no longer control.  If that happens, then the transaction won't propagate across the network and will never confirm.

If you are absolutely certain that the unspent outputs that your wallet currently knows about are still available for your wallet to send, then go ahead and send the transaction.  It isn't necessary to wait for the sync to complete, it just helps to avoid confusion and "stuck" transactions in those situations where the outputs are already spent without your knowledge.

Note that if you have any bitcoins left in your wallet after you send the transaction then some of your balance will probably return to your wallet as change from the transaction.  Since this change will be part of the transaction that you sent, that amount will be unconfirmed until the sync completes.  Depending on what percentage of your remaining balance ends up as change, you may find that you can only send 1 transaction before you have to wait for enough of your balance to confirm to be able to send a second transaction.  In that case, you won't be able to send a second transaction until your wallet has caught up with synchronization.

It is possible to send the second transaction even if your balance is unconfirmed, but only if you change the settings on the wallet.  Doing so opens you up to risks of "stuck" transactions from transaction malleability.

Update us about this so that we will have a knowledge what will happen.

So I sent the coins with 10 weeks of the blockchain left to download, The transaction is showing up on blockchain.info with 4 confirmations so I guess you can still send bitcoins from an out of sync wallet so the long as the bitcoins are actually still in that wallet.

just leave your computer on, and go do something else during that time.

when you sync it should leave off where it left. unless im wrong here..

You can do that, but it will be sent when your wallet will be synced.

That is not correct - it will be broadcast immediately - you just won't be able to see the tx as confirmed until you have caught up.

correct me if i am wrong but i just want to point out that you can easily check your Bitcoins status on any online explorer out there and see if everything is how you left them a year ago, and then sent the tx

That depends on your UTXOs - you do realise that if you are using bitcoin-qt it *hides* the change addresses?

I'd say the vast majority of people using bitcoin-qt do not understand how it works well enough to be able to find their entire balance by just using say blockchain.info.

You're right. I just want OP to understand that amount of BTC he see in his wallet is obsolete.

Moreover, most of wallets usually contain more addr. and it could be annoying to check them all by hand. I saw a web which summarize BTC on all addr. you put in ... but I can't remember the name

 

You are wrong man. He can do that and it will be sent immediately. Waiting for synced is not necessary.