 
  
Hola Claudio 
Gracias. Aquí va lo que hay echo:  
c:\programas\mysql\mysql server 4.1\bin>mysql -u root -p mysql (enter) 
Respuesta: Enter password: root  (enter) 
Welcome to the MySql monitor. Commands with ; or  \g.
Your Mysql connection id is 1 to server version :4.1.16-nt
Type 'help;' or 'h' for help. Type '\c' to clear the buffer. 
Mysql>SET PASSWORD FOR 'root@localhost' = OLD_PASSWORD('root'); (enter) 
Error 1133 (42000) can't find any matching row in the user table 
mysql>select user, host from mysql.user; (enter) 
User  |  host 
root  | localhost 
Que se passa ahora? 
Salud