Question regarding Wallet.dat file saved prior to encription

[TanteStefana]

if you have a wallet.dat file that you saved before you encrypted your wallet, can you still use it to open a wallet up (in other words, is it a loose canon that must be destroyed?) Or is the knowledge that this particular wallet has been encrypted get put on the blockchain or something? Thanks

 

[chaeplin]

I had same question, when wallet said "IMPORTANT: Any previous backups you have made of your wallet file should be replaced with the newly generated, encrypted wallet file. For security reasons, previous backups of the unencrypted wallet file will become useless as soon as you start using the new, encrypted wallet."

wallet.dat before encryt = encrypted wallet.dat which spent nothing after encryt
I think meaning of "as soon as you start using the new, encrypted wallet" is "as soon as you send money using the new, encrypted wallet"


from reddit.
http://www.reddit.com/r/dogecoin/comments/1x7vhp/please_explain_something_important_to_me/

ninja shibe

Yes you are right but I would add this:

When you set an encryption key for your wallet, all unused keys in it get marked as used, so they won't be handed out to satisfy requests for new addresses. This is to keep you from getting money sent to potentially unsafe keys. However, the keys are not marked invalid or discarded, so if you do manage to get one (using pywallet or db_dump or something), you can still use money sent to it.

Now, with all of the keys marked as used, your node needs to generate a bunch of new keys for the keypool, so that it can give you addresses without asking for the encryption key again*. This means that your wallet now has a bunch of keys in it that are not in the backup you made before encrypting. If you ask for a new key, and then restore from your backup, any money sent to that key will be lost and gone forever. So, right about now is a very good time to try to scare you into making a new backup.

The reason the message says that your wallet won't work any more is because people don't want to read a detailed essay on wallet key and backup management. The message just needs to convince people to make new backups, not necessarily go into all of the gory details about how and why.

If you can think of a concise message (that is also easily translatable) that is likely to get people to make new backups, without technically being a lie, please suggest one.

 

[TanteStefana]

Thank you Chaeplin!

 

[vertoe]

Its pretty simple, just imagine: The wallet.dat is a box with a couple of private/public keypairs.

All you need to spend your coins is the private key.

You have an unencrypted wallet backup with keypairs A, B and C. You encrypt your wallet and create new keypairs D and E. You have both backups floating around somewhere encrypted (A,B,C,D,E) and the older unencrypted (A,B,C) wallet.

If an attacker manages to compromize your backups he will be able to access the unencrypted private keys for A, B and C using your unencrypted backup. It doesnt matter that you encrypted these keypairs later as long as you have unencrypted backups floating around somewhere.

TL;DR don't save unencrypted backups at all.

 

[TanteStefana]

Clear! Thanks!