Strange transactions to unknown addresses....

[amex4152]

 Hello All,

 I'm a little worried, I have been moving some of my coins beetwen my desktop wallet and a wallet on blockchain, and it seems to be a third address where part of my bitcoins are ending, look

My Desktop address:
1LfjvP7xxonxGUCCiMqRWvQT5SiMcZ2mDZ

My bitcoinchain address:

1EYX6Sxrw2bicHR5UZKBgZfsgGq9WjGDr3


 On my desktop client, at the moment, It shows the quantity of

0.20816852 BTC

 But, on https://blockchain.info/address/1LfjvP7xxonxGUCCiMqRWvQT5SiMcZ2mDZ , shows only

0.15986852 BTC


 the missing quantity seems to be on

163o2so6dM2UDGsMG1NSpvhcfjVnLJqugx

 It happened before, with address 12oZvG8wC5HFedHidpj7Z6dZ6fudBhCxQ4 , that time I panicked and transfered all to the bitcoinchain wallet, and the missing bitcoins get to the final address....

 So... Should I be worried, is this normal ? Do I get hacked ?


 Thanks in advance.

[DeathAndTaxes]

It is a concept called "change".  Bitcoin works on independent inputs and outputs.  To spend an output worth 1 BTC you must spend EXACTLY 1 BTC.  If you wanted to send only say 0.3 BTC your wallet would create a tx with a 1 BTC input and two outputs, 0.3 BTC to whoever you want to pay and 0.7 BTC back to yourself.

In this case 163o2so6dM2UDGsMG1NSpvhcfjVnLJqugx was a change address in your wallet.  


More info here:
https://en.bitcoin.it/wiki/Change

Nothing you posted indicates you have been hacked or anything is wrong.

[Rodyland]

Given it looks like you still control the coins, I expect it's the change address from a previous transaction.

Read up on change and change addresses on the wiki.

[amex4152]

Thank you!

 I'll start from there

 

[drawingthesun]

Is there a warning on the client yet about exporting private keys?

If you have a few Bitcoin addresses in your receive payments list and you export only those and delete the wallet file, its likely you have just deleted access to your Bitcoins and this has happened to many people. A lot of your Bitcoins end up residing in these change addresses that are hidden from the user. Remember, before exporting any amount of Bitcoin onto a paper wallet or something, check the addresses balance on blockchain.info to confirm the balance.

[DeathAndTaxes]

Is there a warning on the client yet about exporting private keys?

If you have a few Bitcoin addresses in your receive payments list and you export only those and delete the wallet file, its likely you have just deleted access to your Bitcoins and this has happened to many people. A lot of your Bitcoins end up residing in these change addresses that are hidden from the user. Remember, before exporting any amount of Bitcoin onto a paper wallet or something, check the addresses balance on blockchain.info to confirm the balance.

I would strongly recommend NOT exporting because of this and other potential problems.
Make a paper wallet with a brand new address.  Send the coins from your wallet to the new address (as a normal transaction).

To answer your direct question there is no warning.

[amex4152]

Thank you guys, I think I understand now what's happening, will follow DeathAndTaxes advice.


 Regards.

[drawingthesun]

Is there a warning on the client yet about exporting private keys?

If you have a few Bitcoin addresses in your receive payments list and you export only those and delete the wallet file, its likely you have just deleted access to your Bitcoins and this has happened to many people. A lot of your Bitcoins end up residing in these change addresses that are hidden from the user. Remember, before exporting any amount of Bitcoin onto a paper wallet or something, check the addresses balance on blockchain.info to confirm the balance.

I would strongly recommend NOT exporting because of this and other potential problems.
Make a paper wallet with a brand new address.  Send the coins from your wallet to the nee address.

To answer your direct question there is no warning.

Thanks D&T. Hopefully all the current literature on exporting paper addresses follows your recommendation. Making a new address for the purpose of exporting and then sending the coins to that address is certainly the best approach. I remember reading about people losing coins because of assumptions about the software that are not clear and I hope it doesn't happen anymore. Posts like the OP remind me how little newcomers know about the system and how that can cause them financial loss if they assume the apparent workings of Bitcoin from the GUI in the client.

[amex4152]

 A little embarrassing note, I'm not really newcomer to bitcoins, I returned from a couple of years ago, and the funny thing, that was the root of my problem, since I imported my very old wallet into a new environment, for the second time.

 So, there you go.

 Again, thank you guys...

Regards.

[drawingthesun]

A little embarrassing note, I'm not really newcomer to bitcoins, I returned from a couple of years ago, and the funny thing, that was the root of my problem, since I imported my very old wallet into a new environment, for the second time.

 So, there you go.

 Again, thank you guys...

Regards.

Not embarrassing at all. I spend far too much time here its abnormal.

Good luck!