After Windows updated the synaptics software had this problem.
I was able to resolve this issue by doing the following.
In the control panel go into the Mouse settings. Choose the tab for Device Settings (has red icon to left) and go into settings.
The option to choose is Virtual Scrolling and make sure tick is in the box for Enable vertical scrolling.
Hope this resolves your problem.
Message Edited by netten on 02-25-2009 09:18 AM