Click the tool gear icon in the upper-right corner of the IE9, and in the pop-up Drop-down menu, select Manage Add-ins. The following figure appears:
Search provider
Click on the "Search provider" feature item on the left side of the interface to see the existing link search engine listed in the "name" on the right. Users can view the currently available searches here, and users can add the programs they need to customize more search providers.
Users simply check the "Prevent program from recommending changes to my default search provider" checkbox to lock IE9 's default search engine and prevent other programs from changing the default search engine.
Don't meddle with my default search engine
In addition, you can also add other search engines to the IE9 browser by clicking the Find more Search providers button under the search provider, such as Microsoft's own Bing search engine, Baidu searches commonly used by domestic users, or other professional search engines such as weather search, online shopping search, music search, etc.
Add more Search Engines
These features search services are essential to make your IE9 browser more usable.
Summary: "Manage Add-ins" is a very important function of IE9, through the use of this feature can solve the IE use of many problems, but also very simple and effective.