browser redirecting XP home

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When i use hotmail or yahoo messnger, and try and go to the mail, a blank
screen appears. even when i go to the yahoo site direct and go to mail it
signs in, then then next screen say something like "your browser setting
prevent you from viewing this page" I have reset all the defaults and run
Ad-Aware and AVG virus checker, but still wont let me in. i have the same
setup on a laptop with no problems.
anyhelp would be gratful

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