That's one of your best weapons in fighting a non-cooperating website--check another computer! or borrow a friend's or neighbors or at school or a work computer. Web administrators are very apt to deny there is anything wrong with their website as they are the authors! They think their stuff never breaks or is impervious from cyber-attack, etc.
For example, when Microsoft caught the first worm e-mail virus back in 1998 (the I Love You Virus), they refused to believe that their website was at fault; until 10,000 businesses (including mine) called in all on day one and reported it. After that, they had to take steps to remediate--however, their steps included shutting down Hotmail and MSN E-mail as well as Corporate MS Mail for 4 days!!!
Just sayin'...don't always listen to those guys. Sites like WOT and Symantec Reputation toolbar help with figuring things out.
Cheers!
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