How to remove data and passwords from prior MySQL installations
The previous password and all the data must be removed if the password was forgotten.
MySQL server was installed, and then removed.
First, you must find the location of the files to delete.
Method 1 of finding the files:
Start the MySQL Installer, may navigate through all programs
When installing, you may notice the location where the data was stored. While on the Installation tab, “Show Details >” and scroll up to see the installation directory.
Method 2 of finding the files:
Open Windows Explorer to browse to a directory.
Type in the Address %appdata% or %programfiles%
Removing the Data:
Uninstall MySQL Server.
Delete the folders that contained MySQL.
Open Command line in admin mode.
Open the start menu > All programs > Accessories > Right click Command Prompt > Open in admin mode
Use the cd.. and cd FOLDER_NAME commands to navigate to the folder to delete
Use the del /s MySQL command to delete the data and everything in it.