By Judy Vorfeld
Different from: This product is different from the one I normally use.
Different than: I see the issue in a different way than you do. (Although “from” is normally preferred, “than” is acceptable in order to avoid sentences like, “I see the issue in a different way from the way in which you do.”)
If I understand Gregg, try not to say “different than,” without using a word or words like “way” or “manner,” etc. in between. Otherwise, use “different from.”
Using this example, you might either say “I am different from you,” or “I am a different kind of person than you.” I like the second a bit better, but either is fine.
The Gregg Reference Manual