Can you post a link to a page where you see that happen?

Such errors are sometimes in the page source as the result of pasting content from one encoding to another encoding and in that case there is nothing that you can do.

example of page: http://scienceofdoom.com/2010/09/17/on-missing-the-point-by-chilingar-et-al-2008/

- a little over half way down, the section headed "Anthropogenic Imact on the Earth’s Climate – Tiny"  from  paragraph "And continue: " there are these non-characters in the equation (12) and subsequently.

Another page : http://www.zimbabwesituation.com/sep26_2010.html in the topic " Red warning lights" . Most web-pages I read are without problem. I contacted the writer of the first page and s/he had no idea why it happens.

I've got the same thing happening. About 90% of the time, it's an apostrophe (') showing incorrectly, and the rest, it's an ampersand (&).

Do you see all the punctuation here?

• http://en.wikipedia.org/wiki/Punctuation

Does it help if you disable website fonts and try a few different default fonts?

• Tools > Options > Content : Fonts & Colors > Advanced