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you don't actually need to worry much as there are some scripts which you can perform on your PC which can take out the password from .dat file.
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Its not as easy as you might think.
Lets say you have a good randomly generated password with 6 alphanumerical symbols [a-z,A-Z,0-9] and remember nothing about it. Thats 8
62 possible combinations. With 1600 passwords checked per second (its roughly what my GPU does on bitcoin core wallet files) it would take 1.9*10
45 years to crack the password. Testing a few million passwords is no problem though, but you will have to remember a lot about your password to get there.
You can´t check 1600 passwords a second, sorry to dissapoint you. Most properly written encryption software will allow 1 per second if the iterations are set high. In your case, you may need the help of a professional. If you had a passphrase with a high bit rate you are going to have to remember a good portion of your password, and then a script can be written to attack it. Again though, if the encryption for the wallet was written propertly, you may only be able to try 1 password per second. I used a script written by someone else to crack my LUKS encryption password to a flashdrive. I knew what the pw was. just didn´t know what symbols I added to the beginning and end. I was able to incorporate the symbols I thought were used in the script and after several days i got it. however, i knew most of the passphrase. LUKS encryption only allows you to try 1 password per second because of high iterations.
The other option may be to try to do a forensic search to see if the password was cached somewhere? This is unlikely however, as good encryption software prevents this from happening.