Cannot reset a password on Mac

[user19]

Hello. My situation is the following: there was a water spilled on an open MacBook connected to a power supply.
The nearest computer service said that the keyboard and battery were burned out. After replacing the battery and keyboard the password stopped working. The password is known and 100% correct; it is entered correctly (and we did not tell the password to the repairer because he did not even need it).

Two questions 1. What could have happened? Why did the password change? 2. Attempting to obtain a password through the command to reset the password in the terminal and entering the password from Apple ID gives you the following answer: “The given iCloud account could not unlock this volume”.

Are there any other ways to unlock the Mac without installing MacOS newly again (and losing all the data on the device)?

Thank you!

 

[Fishrrman]

It sure helps when you tell us WHICH MacBook you have and what year it was made...

 

[richard2]

The most likely explanations are that you are unwittingly entering the password incorrectly, or that the contents of the internal storage device was corrupted by the accident. The former could occur if the wrong input source (keyboard layout) is set, or if one of the keys is faulty.

Try the following:

1. Boot macOS in recovery mode.
2. Click on the flag icon on the menubar, and then choose the input source that was in use when the password was set.
3. Choose Utilities → Terminal from the menubar. (Terminal will serve as a substitute for TextEdit.)
4. Press shift-command-I.
5. Type the password.
6. Verify that the input text matches the password.

 

[Honza1]

Try with external USB keyboard? #3 suggestion above is probably best, but if you would have usb keyboard around, it could work. Depends on what symbols you have in the password and what layout is needed. Personally, I always try to use standard characters for passwords, not local unique characters requiring keyboard special layout.