CCleaner is a freeware system optimization and privacy tool. It removes unused files from your system - allowing Windows to run faster and freeing up valuable hard disk space. It also cleans traces of your online activities such as your Internet history.
Cleans the following:
Internet Explorer
Temporary files, URL history, cookies, Autocomplete form history, index.dat.
Firefox
Temporary files, URL history, cookies, download history.
Windows
Recycle Bin, Recent Documents, Temporary files and Log files.
Registry cleaner
Advanced features to remove unused and old entries, including File Extensions, ActiveX Controls, ClassIDs, ProgIDs, Uninstallers, Shared DLLs, Fonts, Help Files, Application Paths, Icons, Invalid Shortcuts and more... also comes with a comprehensive backup feature.
Third-party applications
Removes temp files and recent file lists (MRUs) from many apps including Opera, Media Player, eMule, Kazaa, Google Toolbar, Netscape, MS Office, Nero, Adobe Acrobat, WinRAR, WinAce, WinZip and many more...
I don't know how you are browsing, but I never had the problems you are having. I assume, you have a HIJACKER on your computer.
I would suggest, try:
Download ewido security suite here: http://www.ewido.net/en/download/
Install and update it.
Add the install instructions for Ewido:
1. When installing, under ''Additional Options'' uncheck ''Install background guard'' and ''Install scan via context menu''.
2. When you run ewido for the first time, you will get a warning ''Database could not be found!''. Click OK. We will fix this in a moment.
3. From the main ewido screen, click on update in the left menu, then click the Start update button.
4. After the update finishes (the status bar at the bottom will display ''Update successful'')
5. Exit Ewido.
You can eliminate the symptoms with CCleaner, but can't find the cure.
In other words, it cleans your system thoroughly. But then ,one minute later after your first Google search you have your browser redirect to unwanted, privacy-stealing shopping sites.

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