This is a software which allows you to clean your computer . The junk files in your computer will be cleaned. The Registry will be cleaned and fixed as if some of the deleted/uninstalled programs will leave some indexes in your computer.
They will be cleaned completely by the ccleaner. The ccleaner is a perfect pc cleaner. it will give your computer the speed and the best performance. here im using this software since 4 years. as I have no problems with this software. and no restriction in cleaning your pc completely.