usually, in my experience, the little square thing or other annoying characters that don't belong there, replace quotation marks and question marks or apostrophes.
i just export the document (or convert it) to a word/open office document where i perform a search and replace by selecting the irritant and replacing all with what's supposed to be there. (this, in the case where all ", ', or ? or etc are replaced by the same annoying character)
hope it makes sense
