Problems loggin in

I am having problems logging in to a site. The is an admin account and it doesn’t tell anything is wrong, it just loops back to the login screen. If I type in the wrong password i get an appropriate error.

If I request a new password I can get in but only that one time. I’ve changed the username, added usernames etc but none work unless I request a new password. Strange.

I do have one editor and that personal can login with no problems.

For a while I thought it was my computer but I had a windows crash and had to reinstall. Still have the same problem. This started just in the past couple of weeks.

I’m running WP 3.04. Anyone have any ideas? I don’t think its a plugin but I’ve avoided that because the site is busy. I’d have to do it late at night.

Thanks