You are not seeing an error just login failure?
Are you sure you didn't change the password when it was running on your local machine? I would look in the mp_Users table and verify your password. Also make sure FailedPasswordAttemptCount is 0 and IsLockedOut is 0.
If you previously set it to encrypt passwords then you may need to manually change that back in the mp_Sites table by setting PasswordFormat = 0 then manually set a new password in mp_Users table. Once you get it working again you can set it back to use encrypted passwords if you want to.
If there is any error happening you can find it in /Data/currentlog.config file
Hope it helps,
Joe