filling in pdf forms

Using Acrobat Reader, I filled in my answers to several questions. Once done, I tabbed to the net dialog box, filled in my answer to the next question. The box was white with black letters. But when I tabbed to the next question, the previous box turned blue again. On and on it went, so that every box was text in a blue-hued box. I printed out the document and everything text box printed perfectly. But then I e-mailed the completed form to myself, and the document when opened was completely blank. I have tried to re-enter text in some of the boxes, but eventually they all turn blue again. How can I remove the blue background from the text boxes?