Im a fool, encrypted wallet.dat , need advice

[BitshireHashaway]

To brute force a password that is 15 characters (assuming it has numbers, lower, and uppercase letters would take forever, literally:

Time Required to Exhaustively Search this Password's Space:
Online Attack Scenario:
(Assuming one thousand guesses per second)   2.48 hundred trillion centuries
Offline Fast Attack Scenario:
(Assuming one hundred billion guesses per second)   2.48 million centuries
Massive Cracking Array Scenario:
(Assuming one hundred trillion guesses per second)   2.48 thousand centuries

I would think that could be quicker based on some of the things that the OP said they know. If you use an offline very fast set of computers I would say you could get it (hopefully in a few years tops:))... is it worth it depends on how many coins in it.

[Chronic1]

well its max 15 charachters long, only 1 capital letter , only 1 symbol if even. Only 20 character's possible in the set

[bitcoiner49er]

See here:
https://bitcointalk.org/index.php?topic=85495.0

If you can remember "most" of it, you should be able to get into it.

[Galahad]

If the worst happens you only have 2 BTC in there so you could put it down to experience and move on, (but I would hate doing that as well.)

[Chronic1]

$250 is one expensive lesson

[DannyHamilton]

- snip -
characters used to about 20, I know where the only upper case letter is, and i know it can contain only 1 of 4 possible symbols at max.
The password is between 8 and 15 characters.
- snip -

With a passphrase made up of 8 random characters drawn from a set of 24 possible characters (20 + 4 symbols) you are looking at 110,075,314,176 possible combinations.

I'm not certain, but that might be possible.  Even better if you know that there is definitely one and only one symbol in the passphrase. Better yet if you can remember any specific characters that were definitely in the passphrase, and much better if you can remember any specific locations of any of hose characters that were definitely in the passphrase.

Really, the more you can remember about the passphrase, the easier brute forcing becomes.  Remember a sequence of 2 or 3 characters that were definitely somewhere in the passphrase (such as "ed3k"), and you chances start to look really good.  Remembering the length to a better specification than "between 8 and 20 characters" would help a lot as well.

Now, if you are looking at a passphrase made up of 15 random characters drawn from a set of 24 possible characters, you are looking at about 504,857,280,000,000,000,000 possible combinations.  This is MUCH MUCH less likely to be brute forcible if you can't remember much else about the passphrase.

[timeofmind]

well its max 15 charachters long, only 1 capital letter , only 1 symbol if even. Only 20 character's possible in the set

Wow, you really remember almost nothing about it, do you? You can't even remember if there was a symbol in it or not? Sounds like total amnesia.

[DannyHamilton]

well its max 15 charachters long, only 1 capital letter , only 1 symbol if even. Only 20 character's possible in the set

Sorry, didn't see this post until after I made my previous.

So it's definitely 15 characters?  That's going to make it tough unless you can remember more about it.  It helps that a symbol only occurs once, but even ignoring the potential symbols for the moment, just the fact of 15 characters drawn from a set of 20 possible is probably more than you are going to reasonably brute force.  Perhaps some meditation and visualization will help you recall more facts about the passphrase?

[Energizer]

I experienced the same problem before. My advice to you is try to remember the password. Think in a simple/easy way, do not make the situation worse by trying to remember more complex passwords that you would have used. I remembered my password away from the computer/keyboard. Trying multiple failure passwords would make it much harder for you to remember. Good Luck!

[Chronic1]

Well Im certain its either a typo in a password I use for everything or else its something quite easy, which would have one capital and only one numeral which I know at the end and only uses alphabetic characters(all lower case except for the one capital), eitherway I think I remeber the first 5 or 6 characters at least. Im sure I could narrow it down more, would I have to script my own brute-force app or is there something I can use?

I reckon if I had the right software I could play around with the parameters to get it.

Thanks for all the replies, appreciate it!

[reich]

You got a lot of help on this thread, you should be able to retrieve it if u know some of it

[reich]

Have you recoved it yet?

[Chronic1]

Nope, just got home , ive been trying everything possible but I think im starting to confuse what I had remembered with what I've being trying

[Chronic1]

Id almost give out my .dat just out of interest to see if anyone can hack it, doubt ill be able to get it open

[DannyHamilton]

Nope, just got home , ive been trying everything possible but I think im starting to confuse what I had remembered with what I've being trying

Stop trying.  You'll only confuse yourself more and make it harder to remember.

Start by assuming that the coins are gone for good and coming to grips with the loss.  Hoping that you can recover them is increasing your anxiety at the possibility, and delaying the process of overcoming panic.

Next sit in a quiet room.  Turn on some of your favorite music.  Get a pen and paper.  Try to clear your mind of any other concerns you have right now.

Think back to the date and time when the password was entered.  Don't try to remember the password.  Don't try to remember anything you were doing with your wallet. Think about other things you were doing at that time.  Where were you sitting? What time of day was it? What was the weather like? Was the TV on?  Was there anyone else around?  Scent is strongly linked to memory.  Was dinner cooking? Were you drinking coffee? Was someone wearing perfume/cologne nearby?  What had you been doing before you started messing with your wallet?  What did you do after you finished messing with your wallet?

Now that you've got your mind focused on the day and time and various memory triggers surrounding the wallet, close your eyes and think out what you saw on the screen.  Can you visualize any of it?  Where on the screen was your wallet located?  What other programs (if any) did you have open at the time?  Picture the window for entering your password as best you can remember it.

Now, what fuzzy things do you remember about the password?  Approximate length, sounds or letters that caught your attention.  ("there's a z in there? huh, that's unusual", "trmp, hmm, that almost looks/sounds like tramp", etc).  What specifics do you remember.  (First letter?  First 2 letters?  Last letter?  Last 3 letters?,  "It definitely has the following letters somewhere in the middle.", "I remember these 2 (or 3) letters were all together in this order.").

Write down whatever you can remember.  Get it on paper so that later when you are trying variations you don't mix up what you remembered with what you tried.

Once you've spent some time relaxing, focusing, visualizing, and writing, get some sleep.  Go to bed and drift off while thinking about what else if anything you can remember about the password.  Keep paper and pen next to the bed.  When you wake up (in the middle of the night and/or in the morning) think for a moment about your password and if there is anything new you remember about it.

Now take that paper and use the information from it to configure a brute force script (there are a few good ones in the forum, you can search for them or write your own).

The more information you can remember the more likely you are to reduce the possibilities to something that can be brute forced.  Just remembering the position of a single additional character can make a HUGE difference in the amount of effort necessary.  It you can't write or configure a script on your own, find a trusted member of the forum who can help you.  There are several well trusted members with both the ability and interest in helping you get a script up and running if they think there is a possibility of recovering the password with the info you can provide.

There are even some who you can trust with your wallet.dat who will run the script for you and send you the bitcoins if they succeed.

[ranlo]

I experienced the same problem before. My advice to you is try to remember the password. Think in a simple/easy way, do not make the situation worse by trying to remember more complex passwords that you would have used. I remembered my password away from the computer/keyboard. Trying multiple failure passwords would make it much harder for you to remember. Good Luck!

To add on to this, don't let your fear of loss bother you. Fear causes chemical reactions in the brain that causes decreased thought ability ("fight or flight"). It's the same problem a lot of people have with tests.

Just let it go and occasionally it will come back to you (or should).

The more you work yourself up about it the harder it's going to be to remember.

[xetsu]

I don't know what to tell u man, hope you get it solved. Thats the problem with passwords for stuff like this you can forget whenever. just like people here recommend having an offline bitcoin address, I have an offline computer where i keep all my passwords offline and off the net. Best bet is just ot have a usb drive/harddrive/sd card with an os and the information and keep it hidden in your house. that way someone has to physically go to your house, locate that usb/sd card, launch it, etc.

[DannyHamilton]

15 letters, seems like way to much, a simple 4 character passcode is far enough.

This is HORRIBLE advice.  Please, please, nobody take this advice.  If you are going to do this, then don't even bother encrypting your wallet.  You'll just give yourself a false sense of security and be more likely to engage in actions that will compromise your wallet.

[Chronic1]

Nope, just got home , ive been trying everything possible but I think im starting to confuse what I had remembered with what I've being trying

Stop trying.  You'll only confuse yourself more and make it harder to remember.

Start by assuming that the coins are gone for good and coming to grips with the loss.  Hoping that you can recover them is increasing your anxiety at the possibility, and delaying the process of overcoming panic.

Next sit in a quiet room.  Turn on some of your favorite music.  Get a pen and paper.  Try to clear your mind of any other concerns you have right now.

Think back to the date and time when the password was entered.  Don't try to remember the password.  Don't try to remember anything you were doing with your wallet. Think about other things you were doing at that time.  Where were you sitting? What time of day was it? What was the weather like? Was the TV on?  Was there anyone else around?  Scent is strongly linked to memory.  Was dinner cooking? Were you drinking coffee? Was someone wearing perfume/cologne nearby?  What had you been doing before you started messing with your wallet?  What did you do after you finished messing with your wallet?

Now that you've got your mind focused on the day and time and various memory triggers surrounding the wallet, close your eyes and think out what you saw on the screen.  Can you visualize any of it?  Where on the screen was your wallet located?  What other programs (if any) did you have open at the time?  Picture the window for entering your password as best you can remember it.

Now, what fuzzy things do you remember about the password?  Approximate length, sounds or letters that caught your attention.  ("there's a z in there? huh, that's unusual", "trmp, hmm, that almost looks/sounds like tramp", etc).  What specifics do you remember.  (First letter?  First 2 letters?  Last letter?  Last 3 letters?,  "It definitely has the following letters somewhere in the middle.", "I remember these 2 (or 3) letters were all together in this order.").

Write down whatever you can remember.  Get it on paper so that later when you are trying variations you don't mix up what you remembered with what you tried.

Once you've spent some time relaxing, focusing, visualizing, and writing, get some sleep.  Go to bed and drift off while thinking about what else if anything you can remember about the password.  Keep paper and pen next to the bed.  When you wake up (in the middle of the night and/or in the morning) think for a moment about your password and if there is anything new you remember about it.

Now take that paper and use the information from it to configure a brute force script (there are a few good ones in the forum, you can search for them or write your own).

The more information you can remember the more likely you are to reduce the possibilities to something that can be brute forced.  Just remembering the position of a single additional character can make a HUGE difference in the amount of effort necessary.  It you can't write or configure a script on your own, find a trusted member of the forum who can help you.  There are several well trusted members with both the ability and interest in helping you get a script up and running if they think there is a possibility of recovering the password with the info you can provide.

There are even some who you can trust with your wallet.dat who will run the script for you and send you the bitcoins if they succeed.

Thanks for the advice, ill try forget about it for the meantime and then try recreate the situation.

[BTCoder]

Good luck retrieving your coins!