What is NaviSearch?
What is it?
NaviSearch is adware that displays search listings in a background window. NaviSearch listings are displayed as a "search helper" when a user has typed text into the address bar or search boxes of their web browser that would normally resolve to a "404 Page not found". The NaviSearch search helper tries to deduce what content the user was searching for, and present relevant ad-supported sponsored results.
Why should I uninstall NaviSearch?
NaviSearch is an adware program that serves undesirable commercial advertisements and pop-ups. It also changes the Internet Explorer default search page and related settings. NaviSearch is bundled with some ad-supported software.
Typical installation path: C:\Program Files\navisearch\
How to Automatically Uninstall NaviSearch (with Boost)
If you you do not have Boost installed yet, download Boost and enjoy your PC.
Open Boost by either double-clicking the Boost icon 
in your notification area next to your PC's clock, or single-clicking the Boost icon and clicking the Open Boost button on the top left of the Boost notification window.
If you are not currently on the My PC screen of the main Boost window, click the My PC tab.
Click the Optimize programs button 
, this will launch the Program Optimization screen.
Locate the program in the list called NaviSearch . (The program could be listed under any of the section such as Uninstall Recommended, Possible Uninstall, etc. based on how well NaviSearch performs on your PC.)
NaviSearch
To the right of the list item, click the Uninstall 
button and Boost will completely remove NaviSearch from your PC.
How to Manually Uninstall NaviSearch (with Windows)
Use Add/Remove Programs control panel in Windows makes to uninstall NaviSearch. Follow the appropriate instructions below to use this control panel.
Windows 7
From the Start menu, select Control Panel.
In Large or Small icon view, click Programs and Features. If you're using Category view, under "Programs", click Uninstall a program.
Select NaviSearch from the list of programs, and click Uninstall. Alternatively, right-click the program and select Uninstall.
Windows Vista
From the Start menu, select Control Panel.
In Classic View, double-click Programs and Features. In Control Panel Home view, under "Programs", click Uninstall a program.
Select NaviSearch from the program list, and click Uninstall. Alternatively, right-click the program and select Uninstall.
Windows XP
From the Start menu, select Control Panel.
Click the Add or Remove Programs icon.
Select NaviSearch from the list of programs and click Remove.