Hello I lost 4 words from my 12 word phrase, didnt used it quite long time and now I see I have only 8 of 12 words for the old wallet where I sent a few years cardano on it. My Harddisk died so I wasnt able to get to them quite long. Now I see there are oppurtunities with a program or sth.
Is there a list of the words which are used since this time?
The list linked in the post above yours is still the same.
There are 2048 possible words. 2048^4 combinations are almost too much to try. This will be cut down by the checksum in the seed phrase, but not enough, I fear.
One tool you could try is BTCRecover: https://btcrecover.readthedocs.io/en/latest/Usage_Examples/basic_seed_recoveries/#basic-cardano-recoveries
Is it a Byron or a Shelley wallet?
It is a Byron wallet, because it was made in 2019.
That makes it worse. As you can see in the link, Byron-era is not supported by BTCRecover (and, by the way, also not by my PySeedRecover, https://github.com/HeptaSean/PySeedRecover).
Even if it were, it would probably take too long, but I don’t even know a ready-made tool that could try it.
(Getting possible valid seed phrases is not the problem. The problem is that they are far too many and a tool would need to derive addresses from them to automatically compare to a known one.)
Is there really no other way? Rescuing files from the dead HD? A second copy of the seed somewhere?
I think I overwrited the HD. But Iam not sure. The problem is that this HD is in another country, so I could only try to find some files in near future.
The better way would be to find a tool where I can pythonize the 4 last words. The paper where I writed everything down is not complete anymore.
I could find out the address because I know from where I send some Ada there. No chance that I have a copy of it. I assume it was Byron because there was no Shelley in 2019. Staking wasnt even available during this time.
Thanks for helping me out. If there is an opportunity, I could wait aswell some years if it takes so long to pythonize it.
Greets
Hello Hepta,
Now I found out, it is a shelley wallet.
I have now the wallet address, it starts with addr1
How can I use this tool to restore the last 4 words?
Sorry for the delay.
That cannot be if it is Daedalus. Daedalus used 12 words exclusively for Byron era wallets. If it is a Daedalus Shelley wallet, it has to have 24 word seed phrase.
Which could also be a glimmer of hope that you just have to find the other seed phrase used for the Shelley wallet that you maybe stored somewhere else and that maybe also is complete.
Check the address on cardanoscan.io. Find out, when you first used that wallet, when the first transactions come in. Try to remember what you were doing when creating it and where you might have put the seed phrase.
Four words are probably much too many to check.
The effort is multiplied by 2048 for each additional word missing. One word needs a couple of seconds to check, even if it is only one second two words already take half an hour, three words 48.5 days, and four words 272 years.
FWIW, with my tool, usage would be:
$ seedrecover -l 12 -m 9 10 11 12 -a stake1u9xvdasrhvc8zxd6vadvtssvg5yggk5apnp2msplc7eeg9svhcl0c -- abandon about actual age alpha angle argue artwork
abandon => abandon
about => about
actual => actual
age => age
alpha => alpha
angle => angle
argue => argue
artwork => artwork
4 of 12 words missing.
Seed phrases checked: 2_048 total, 128 fulfilled checksum, 128 without repetitions
-l 12 tells it that the length to search for is 12. -m 9 10 11 12 tells it that the missing words should be searched in the last four positions 9 to 12. -a stake1… tells it which stake key to search for. -- ends the options and after that come the 8 known words.
For all of the given words, the words that are tried are shown (this is for the typo fix functionality, if one of the words would not be in the word list or the -s option would be used, there would be closest matches listed).
It then starts to count the checked seed phrases and the ones that fulfilled the checksum and were not previously checked (that is for the reordering functionality, where same seed phrase might be encountered several times).
btcrecover would look similar, but I’d have to check.
But, as said: Searching for four missing words probably takes too long. Up to three might be possible, but that last multiplication by 2048 is too much. And you are probably looking for a 24 word seed phrase.
Thanks for reply.
The last transaction was on 04.01.21
And now how I see they are in a stake pool.
So you say a “addr1” (shelley) wallet adress have only 24 phrases, not 12.
I have to look up.
For remembering, where you stored your seed phrase, the first transaction is much more important. It is usually around the time that you generated the seed phrase and put it somewhere.
Yep. It is theoretically possible to use any length. Some exotic wallet apps (Atomic, Exodus, …) use 12 words for Shelley, but you know you used Daedalus. And there we know that Byron/Ddz is 12 words and Shelley/addr1 is 24 words. Period.
Where could I find the stored secret.key files? And how could I import them? Or are they not supported in the shelley era?
Now I see that it could be that I have 20 from 24 words 
secrets.key are not used anymore. Inside your Daedalus data folder (the one also containing the huge chain/ folder), there is a folder wallets/. That one contains SQLite databases for each of the wallets imported to Daedalus.
If you get access to those, it would probably be easiest to make loads of backups and try to get a Daedalus instance running again using them. Could also be helpful to have the configuration file (~/.config/Daedalus/config.json on Linux, no idea for other platforms), since that tells Daedalus which of those wallet SQLite files to use. (Although, https://iohk.zendesk.com/hc/en-us/articles/900000623463-Importing-wallets says that they should be picked up automatically if they are there.)
Unfortunately, that does not make the task easier. We are still looking at decades here if there is not enough on that wallet to justify renting a supercomputer somewhere.