Good grief, I've never seen anything so ridiculous. I've wasted days on this, and it won't work on any of my Wiindows 7 computers.

Did you install IntelliPoint along with the mouse? If not, do so. If you did, check within it to make sure the correct mouse is selected and the scroll wheel is enabled. SC Tom

Yes I installed Intellipoint. Yes the correct mouse is selected. Don't know where to enable scroll wheel. But I did assign mouse wheel to "Autoscroll". I even installed the bluetooth USB dongel supplied with the mouse. Scroll wheel doesn't work when using built-in bluetooth or supplied bluetooth USB dongle.

Sounds like a defective mouse, then. Take it back for an exchange or refund. SC Tom

See: How to contact Microsoft if you have questions about your Hardware deviceCarey Frisch