My guess is you are using a language other than English and the page being supplied by your mail provider is not necessarily showing all of the page. perhaps if is off the bottom of the screen and you need to scroll, perhaps it has other issues because the language you use requires more space than the provider allowed. Some 30 years ago in the early days of windows I was told at a developer forum that French for instance requires about 30% more space to hold translated information that the English original. Not that I speak from experience as I have no French skills at all.