# In phpMyadmin for the database you wish to you have your phpBB password reset, click the corresponding phpMyAdmin link
# Click the corresponding table that stores username and password information: phpbb_users
# Click Browse located towards the top of your screen so that a list of users display
# Find the account of user that needs to be changed (eg. Admin)
# Click Edit
# From the user_password row, click the Function pull down menu and choose MD5
# In the box to the right of MD5, replace the existing encrypted password with your new password in plain text
# Click the GO button located towards the bottom of the page

Done!