problems with loging in my forum

hi,
i have followed the intrusctions on this web to create a forum
[url]http://www.itcow.com/staticpages/index.php?page=2003032821191223[/url]

but i still got a couple of errors, like logining in problem

everytime any user try to login,
it will display the page cannot be displayed screen
but when back is pressed, the user is loged in

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