In case of forgotten Windows Account Password

1. Boot into a recovery environment/installer
2. Open a command prompt
3. Execute regedit

In regedit

1. Select HKEY_LOCAL_MACHINE
2. On the menu bar, select File -> Load Hive
3. Navigate to <Windows Install Drive>:\Windows\system32\config\ and load SYSTEM
4. Give it a key name, such as 1234 (this way this key block will live on top)
5. Expand HKEY_LOCAL_MACHINE, and go into 1234.
6. Select the Setup keygroup.
7. Set CmdLine to cmd.exe.
8. Set SetupType to 2.
9. Select the 1234 keygroup.
10. Navigate to the File menu and Unload Hive.

Reboot the computer. You will be greeted with a command prompt.

In the cmd

1. List the users: net user
2. Create a new local user: net user NAME PASSWORD /add (Make NAME without space).
3. Add the user to admin: net localgroup Administrators NAME /add
4. Exit the shell: Type in exit and hit enter.

Now you can log in with the local account.