the problem:

When i used the drush dl command i get this erros "cannot login in with user ID #0"

The solution:
Check to see if you have lost the anonymous user row in your drupal users table. if so, manually write an entry for anonymous user. make sure the uid is 0.

alternatively run the sql

INSERT INTO `users` (`uid`, `name`, `pass`, `mail`, `mode`, `sort`, `threshold`, `theme`, `signature`, `created`, `access`, `login`, `status`, `timezone`, `language`, `picture`, `init`, `data`, `signature_format`) VALUES
(0, '', '', '', 0, 0, 0, '', '', 0, 0, 0, 0, NULL, '', '', '', NULL, 1);

Hope this was useful.