Taskbar thumbnails is very useful feature in Windows 7 and most of the time should be helpful for you to see which windows are open and also quickly have a preview of the open windows. Internet Explorer 8 also supports taskbar thumbnails and it shows thumbnails for all the open tabs in Windows 7 taskbar. But in case you have lots of tabs open, this might become an annoying features as Windows 7 shows thumbnails for all the tabs.
Thumbnails for all tabs shown with IE8 icon on taskbar having more than one window.
You can easily disable taskbar thumbnails for individual tabs in IE8. To disable, open IE8 and select Tools-> Internet Options. Under the general tab, click on the settings button under the tabs sub group.
In the tabbed settings, uncheck the box “Show previews for individual tabs in taskbar”. This option requires you to restart IE8. Click OK and restart IE8.
Once you have restarted IE8, you can see only one thumbnail preview even if you have opened more than one tabs in IE8.