I cant sign on most of the time because for...

Try clearing your internet cache(temporary internet files) and deleting cookies. The process to do so is different from browser to browser.

I always set my browsers up to only keep cookies for the "session" and have them set to delete all temporary internet files upon closing the browser to avoid this type of problem.

What cache (temporary internet files) do is they store a version of the website so the next time you go to it, you do not have to redownload the whole page to view it. this cuts down on bandwidth for the site and your ISP. But the bad part of it is that if the page changes, you will not see the changes until you redownload the entire page. This can "most" of the time be remedied by hitting the "refresh" button.