Good morning,
your first option would be to simply crack the password (you will need to have at least user access for this option to work).
You first need to obtain the login information hash (use
Windows PWDUMP tools to get a hash). After downloading pwdump.exe you can just run it via a cmd window and redirect it's output to a hash.txt file on your main drive (like this: PwDump7.exe > C:/hash.txt). I'd recommend to take the file to your machine via a USB stick etc. so that you have more time to actually work on it.
After obtaining the password hash, you can simply run John the Ripper on it. Depending on your system that may take a good while, especially if you can't use your GPU to crack the hash.
John will display all of the usernames and passwords on the target machine after finishing the cracking process.
Your next option would be to bypass / change the password. For this, you need to get into the system repair mode (force shutdown the computer 2 times while it's still booting to get to that option). After performing those two unexpected system shutdowns you'll be booted into the system repair mode. From here you navigate to the advanced options menu and click the troubleshoot button. Click on advanced options again, then select system image recovery.
Here you click cancel. You will then be prompted with a selection for a system image backup, just click next here. When selecting the location of the backup, click on advanced, then install driver, then OK.
You should now have a file explorer running with SYSTEM permissions. Simply insert a USB stick, refresh the drives and remove it again. You now have access to all of the drives. Search all of the drives for the file "Windows/System32/Utilman.exe" and rename it to anything (for example utilman1.exe). Copy cmd.exe and rename the copy to utilman.exe.
After that is done, you can shut down your machine and boot it up normally. You can then click the ease of access button in the login screen for a command prompt with SYSTEM permissions.
From here you can list all users (command is "net user") and reset a user's password (command is: net user "username" *). Leave the password empty to remove the password from the account.
Best regards,
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