I'm not terribly familiar with styles in Word, so I'm not sure if we're talking about the same thing. However, I have had particular Word documents that I used as blanks for other things that repeatedly turned off my spell checking and grammar checking without me specifying it. I could only turn the checkers back on by going to the "set language" menu. Then, when I am using the same document a couple of times later, the checker turns off again. I haven't had this problem in a couple of years, so I was thinking an update must have fixed it.