A new document in Word opens with an old text. How do I clean it?

Answer 1

Go Start>Search and search for a file called normal.dot this is the start up template for a new word document. Delete the file and the next time you start word it will create a new clean normal.dot and your new word documents will be clean.

Answer 2

Because your word files was edited many times. The last time, they (who edited it) saved it in Showing Markup style. When you open it, it will display a lot of red, black, .. with marks and you can not read it properly.
You can chose in View menu (or Review menu) and change this mode (Final Showing Markup) into "Final". You will see a normal view!
That's all!