Does your website pass the W3 Validator 100%? http://validator.w3.org/ any reason to try to aim for 100%? My ads are creating errors.
All pages? To tell you the truth, i don't know. So many changes last weeks, maybe created a error or two.
I generally check the main page and make sure it passes, but then assume the rest will. Some of the more complex codes can cause problems even though they are correct. I'd recommend a copy of htmlvalidator.com. Thats much more fussy but gives a lot of advice and helps to get it right.