Preventing Windows 7 Taskbar Preview

It seems impossible to disable the Taskbar Preview in Windows 7 but the delay before Windows will display the previews can be lengthened:

reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced" /v ExtendedUIHoverTime /t REG_DWORD /d 20000 /f

This causes Windows to wait 20 seconds before displaying the thumbnails.

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