I've just upgraded to version 2.6 of WP from 2.5, and I can't log in as admin with the password that it is. I went into the phpMyAdmin and reset the password (and then changed to MD5) as some support answers have given, and I've even tried the emergency password reset on village-idiot.org to no avail. And of course, this is after attempting the email password reset from the original log-in about 5-6 times.
As a last ditch effort I wondered if perhaps it was because I hadn't filled in the Auth_key, Secure_Auth_Key, and Logged_In_Key info of wp-config earlier-- I filled those with the information at http://api.wordpress.org/secret-key/1.1/ and still nothing.
Umm.. help?? The login screen doesn't even say wrong password, it just keeps repeating: "Please log in again"