This morning I awoke to a new reality - my scroll wheel mouse R-E-F-U-S-E-D to scroll in, as I eventually determined, any html window (ie any web browser, e-mail message formatted in html, etc.). It worked like a charm in all other applications that I tried it in. I tried three other mice, same result (Wacom Bamboo mouse, a Kennsington mobile mouse, and two Microsoft optical units, one wireless the other USB). Very consistent behaviour. I then spent hours disabling IE 8 and rebooting, re-enabling IE 8, messing endlessly with the Mouse applet in Control Panel, removing drivers for my main mouse (MS Wireless Laser Mouse 6000 v.2) and rebooting, uninstalling and re-installing MS Intellipoint 8, etc, etc, etc,...
Absolutely no f&@!#>]{ joy! The best I would get is a couple of seconds of normal operation and then all scrolling would disappear again OR the scroll wheel would either jump to the start of the page or the end.
Finally, about 30 minutes ago I installed Wizmouse and everything worked immediately. WTF?
I'm running Win 7 64-bit but live in a 32-bit browser. I did try both Firefox and Opera before determining that the problem is related to html pages.
Any thoughts? I'm happy enough with Wizmouse, but I'd rather not be running a separate process just to get scrolling in my browser!
EDIT: added "RESOLVED" to the title...