Problem: On one or more pages there is a lot of blanks space at the bottom of the page and you can't delete this space.
Cause: This is caused when the wrong style is in effect. In the body of your paper the style should be Normal or Normal No Indent. Word will sometimes leave a lot of blank space at the bottom of a page when other styles are in effect.
Solution: Change the style to Normal. You might need to select the paragraph above the problem and drag down below the problem and then change the style.