Find passwords

Finding Lost Passwords

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Find lost passwords with the ALZip password recovery utility

ALZip allows you to try to recover lost passwords through a brute force attack on the archive. The brute force method checks every possible password against the archive. This is slow but effective, given enough time. The best time to look for passwords is when you go to bed or on vacation.

To start the password retrieval utility and crack the password of an open ZIP file:

1.	On the ALZip menu click Actions > Retrieve Lost Password...

2.	The "Retrieve lost password" utility opens

Click any area on the following image for more information on it.

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Search symbols

Here you can check which symbols to use while trying to retrieve a lost password. Selecting more checkboxes takes longer.

Password length

Specify the number of characters (as a range) for the ALZip password retriever to try. The wider the range you specify, the more time it takes.

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Password starts with...

If you know that the password is a certain length or that the password is alphabetically (dictionary order) higher than something, type it in here.

Example 1) If the password is "qwerty", and you remember that it is 6 letters and that the first letter is "q", then you can enter "qaaaaa". The password retriever will then start with "qaaaaa" then "qaaaab", etc. Now, instead of trying to crack a 6 character password, you're only cracking a 5 character password.

Example 2) If you know that the password is 10 characters long and begins with "mypass", then you can set the "Password starts with" field to "mypassaaaa" or "mypass0000". Here, you have reduced the task from cracking a 10 character password (nigh unto impossible) to a mere 4 characters, which is easily doable.

This takes much less time to than trying to find the password from scratch.

If you don't know the length of a password, then setting the min and max length (as above) and reducing the number of search symbols to check are your only ways to reduce the recovery time.

But if you do know the length, and do know the first couple characters, this is the most powerful way to reduce the recovery time, and can even bring impossibly difficult password recoveries easily withing reach.

Brute Force Progress

Displays the progress status as a percentage, elasped time, and time remaining. Because the password is unknown, this estimate is not 100% accurate - it is only meant to give you an idea about how long it will probably take. The number is derived by calculating the average time it should take, given the parameters you've specified and the relative speed of your computer.

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Start

Starts the ALZip Password Recovery tool and begins searching for the correct password.

Pause

Pauses the ALZip Password Recovery tool and clears all options. You can resume the task after re-specifying the options.

Cancel

Stops the ALZip Password Recovery tool.

Tip: Finding passwords takes a long time with not only the ALZip Recover lost password function, but also with other password cracking tools. Your computer system's specifications greatly affect the length of time it will take to get a lost password back, but limiting the search parameters is the most important factor. For example, in one test on an old 300 MHz computer, retrieving the password bird using only lower case letters took 38 seconds, while using both upper and lower case letters took 50 minutes and 34 seconds. That's a time difference of about 80 times after doubling the number of characters to search through in the search symbols preference.