Summary
When you drag an item and place the mouse cursor near the top or the bottom of the folder browser window, auto-scrolling occurs. In certain situations, it may appear that no scrolling is occurring, but once the mouse cursor is moved out of the auto-scrolling region of the window, all the scrolling happens at once.
Cause
This window repainting issue can be caused by a particular graphics setting in Windows XP and Windows Server 2003.
Workaround
Enable the Adjust for best appearance option on the Visual Effects tab of the Performance Options dialog box.
To modify visual effects options