Reset admin password in sitecore back to 'b'

 UPDATE

    [aspnet_Membership] 
SET 
    [Password]='qOvF8m8F2IcWMvfOBjJYHmfLABc=', 
    [PasswordSalt]='OM5gu45RQuJ76itRvkSPFw==', 
    [IsApproved] = '1', 
    [IsLockedOut] = '0'
WHERE 
    UserId IN (
        SELECT UserId FROM dbo.aspnet_Users WHERE UserName = 'sitecore\Admin'
    ) 

or

UPDATE
[aspnet_Membership]
SET
[Password]='qOvF8m8F2IcWMvfOBjJYHmfLABc=',
[PasswordSalt]='OM5gu45RQuJ76itRvkSPFw==',
[IsApproved] = '1',
[IsLockedOut] = '0'
WHERE
UserId IN (
SELECT UserId FROM dbo.aspnet_Users WHERE UserName = 'sitecore\Admin'
)

To see if account is locked:

Select * from
[aspnet_Membership]
WHERE
UserId IN (
SELECT UserId FROM dbo.aspnet_Users WHERE UserName = 'sitecore\Admin'
)

https://sitecore.stackexchange.com/questions/280/is-there-a-way-to-reset-sitecore-admin-password-from-database-level/281