The Internet Explorer error “The page cannot be displayed”
This error message occurs with Internet Explorer version 6 when it cannot find the server or when it encounters HTTP errors 405, 500, 501, or 505. Look at the title bar at the top of your Internet Explorer window to determine which of these links applies to you.
This error message can occur with browsers other than IEv6 (e.g. Firefox) when a Microsoft ISA server lies between your browser and a server that needs to be accessed.
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Extra information
Internet Explorer versions 7 and 8 give a different error: The webpage cannot be displayedThis error can be embarrassing when it occurs in public places