If a different driver doesn't do the trick consider AlwaysMouseWheel by Nenad HRG. 

http://www.softwareok.com/?seite=Freeware/AlwaysMouseWheel. 

I haven't used it but I really like his Windows Explorer replacement  Q-Dir.  A good thing about his stuff, at least the apps I've looked at, is that they are available as portable apps so can be tested without the install/uninstall aggravation.

Windows 7 Professional, Service Pack 1

Pegasus Mail 4.63 build 325

I had an older (non-Microsoft) mouse which worked properly.  I installed my better (Microsoft) mouse and cannot scroll the folders or message list. I can scroll the message only if the message is HTML; HTML messages can be scrolled in preview mode and with the message open.  What is different in the requirements to scroll non-HTML and HTML?

Thanks, George

Not sure what to tell you George.  I have a Microsoft USB Optical Wheel Mouse and it works to scroll text and html messages as well as contents in other windows.  I also have 10 users with a variety of other mice who haven't reported any issues. 

Is there any chance that the message you noticed the problem with fit in the window when viewed as plain text but didn't when viewed as HTML?  I routinely attempt to scroll in a window that won't scroll because there is nothing to scroll, the contents fit in the window.  I guess I'm trying to bring the text to my sight line rather than move my head.  Must be these dang bifocals.

Thanks Brian for the reply.  No, it is not that the message is complete in the window.  The older mouse worked, this one doesn't ... but the mouse is so much nicer that I'll live with the Pegasus problem.  Perhaps a different driver, but MS doesn't seem to have multiple available.  It just puzzles me that it will work with HTML mail, but not text ... it does scroll in TakeCommandConsole (4DOS current product) which is text ... ???

Ah well, and again, THANKS!

You should check your mouse driver software at Microsoft with Url:

http://www.microsoft.com/hardware/en-ca/d/wheel-mouse-optical

Select operating system, download and install it.

Martin