Quote from: redsn0w on December 06, 2014, 02:59:14 PM

Quote from: guitarplinker on December 06, 2014, 02:57:32 PM

Quote from: casperround on December 06, 2014, 02:53:10 PM

I've messaged Dave via the service and said I would happily pay him, no reply yet.
I had a thought, if I export the dat as a .txt, then change the encrypted private key to a new one that I know, then export to a .dat
Would that work? Like overwriting the original encrypted private key?

That wouldn't work. If you changed the encrypted private key to a new private key with a new password, you would lose access to your old encrypted private key holding the 10BTC worth.

One thing you can do though if you can't figure out the password is keep the wallet.dat file safely backed up - I'm sure that in 10 or 15 years it'll be much easier to crack a 30-40 character password than it is now. That'll definitely be a long time from now, but it might be worth it.

Yeah , I think this is the unique solution for the moment. With the technology of the future maybe you can easily crack the password (but I'm not sure).

The bitcoin-qt uses key stretching for the encryption of the wallet.dat. Somewhere in the wallet.dat is an entry about the number of rounds that are needed for decryption of the private keys. Depending of the speed of the pc which encrypted the wallet.dat it can be 100000 or more rounds of AES256. It's done in this way so that even passwords of short length are very hard to break by brute force!

TL;DR
If you have one or two typos in your password, it could be possible to brute force it. But 30-40 characters are not crackable for a very long time. Sad