Cannot log in in to my site I am having some problems when I try to log in to my drupal site. When I visit http://mysite/user, i am getting redirect to the login page and in my url appears something like this:

user?name=user&amp;pass=111111&amp;form_build_id=form-iCrzIe6KBq1g5MoA3z0JeBI98QU8q2f-FvfcIcp3Cvk&amp;form_id=user_login&amp;op=Log+in

I'm trying to find the problem, but I don't know what to do.

When i restore the site(from my last backup) i can do the login, but when i restart my machine, the problem comes back.

I hope you could give me a hand with this problem.

Regards
I would check /sites/default/settings.php and look into your $cookie_domain = setting - does it match your domain?