Definition:
(formerly Crap Cleaner), developed by Piriform, is a utility program used to clean potentially unwanted files and invalid Windows Registry entries from a computer.A public version 1.01 for the Mac OS X has been releasedalong with a Network Edition.
CCleaner is a system optimization, privacy and cleaning 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. Additionally it contains a fully featured registry cleaner. But the best part is that it’s fast (normally taking less than a second to run) and contains NO Spyware or Adware!
It also comes built in with a registry cleaner, which can check for problems within your registry.
I tried using this application and it made my life easier. It compiles all pc clean up in one application that the built-in windows disk clean up program can’t.
Features
Download Windows installer here
(Current Version 3.7.1900)
Cleans the following Windows components:

Temporary files, history, cookies, super cookies, Autocomplete form history, index.dat files.

Temporary files, history, cookies, super cookies, download history, form history.

Temporary files, history, cookies, super cookies, download history, form history.

Temporary files, history, cookies, super cookies, download history.

Temporary files, history, cookies, super cookies, form history.

K-Meleon, Rockmelt, Flock, Google Chrome Canary, Chromium, SeaMonkey, Chrome Plus, SRWare Iron, Pale Moon, Phoenix, Netscape Navigator, Avant and Maxthon.

Recycle Bin, Recent Documents, Temporary files, Log files, Clipboard, DNS Cache, Error Reporting, Memory Dumps, Jump Lists.

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…

Removes temp files and recent file lists (MRUs) from many apps including Windows Media Player, eMule, Google Toolbar, Microsoft Office, Nero, Adobe Acrobat, WinRAR, WinAce, WinZip and many more…

This software does NOT contain any Spyware, Adware or Viruses.
Safety:
CCleaner was designed from the ground to be safe and secure to use. It has multiple levels of checks in place to ensure that it cannot delete any useful information or documents you may still need. We also certify that it contains no Spyware or Adware.
High Security:
For the super cautious users we also offer secure file erasing. By overwriting the files before deleting them, making it impossible to recover the data.
Multiple Languages:
Thanks to the translators, CCleaner is available in 35 different languages:
English, Albanian, Arabic, Bosnian, Bulgarian, Catalan, Chinese (Simplified), Chinese (Traditional), Czech/Slovak, Danish, Dutch, Finnish, French, Galician, German, Greek, Hebrew, Hungarian, Italian, Japanese, Korean, Lithuanian, Macedonian, Norwegian, Polish, Portuguese, Portuguese (Brazilian), Romanian, Russian, Serbian Cyrillic, Serbian Latin, Slovak, Spanish, Swedish and Turkish.
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