How to bake a chicken?
One thing I wonder is if your oven temperature is accurate? An oven thermometer helps there. As well as a pizza stone to maintain a steady temperature. Also, how big was your chicken? Maybe you didn't cook long enough for the weight.

The method I use is this: Pre-heat the oven to 450. Clean bird, remove innards, truss. Salt (Tbls or so) and pepper or otherwise rub on marinade. Place the bird on a large cast iron skillet and cook for 1 hour. Remove bird and let rest for 10 minutes and meanwhile make a sauce utilizing the remnants in the pan. The skin is brown and the meat is juicy. This method is in Michael Ruhlman's, 'Ratio'. I find it to be a great method for basic roasted chicken.

I usually use a 4 - 5 lb chicken and haven't checked the internal temps since the first few times of using this recipe except for when I'm at or over the upper end.