I'm using Windows XP, and I've had the issue for several versions back. For me it's affecting 4.5.4. I'm using 4.5.3. I think I found the problem. I tried closing as many programs as I could and found that when I close "TaskSwitchXP" http://www.ntwind.com/software/taskswitchxp.html the problem goes away. It starts with windows.
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