Since the Forum went over to the Xenforo format, I've been having scroll issues under IE11 - Win 7, 32 bit. If anyone is experiencing this - add the site to compatibility view. http://windows.microsoft.com/en-us/internet-explorer/use-compatibility-view#ie=ie-11-win-7
Alternatively, you may temporarily disable smooth scrolling under Advance Settings. This is an Advanced User setting.
Adding Wilders to IE11 compatibility view disables the reply rich text editor - unfortunately. So, I've removed it for now and forge on.