Regarding its functions, it does a highly satisfactory job just like its original program. This portable version does create some necessary keys in Windows Registry, but these are deleted when the program is closed, so there will be no trace of it left on the system, as well.

Simply run it from your USB memory stick and you'll have immediate access to all of its features. In fact, you don't even need to install it. The great advantage of CCleaner Portable is that it enables you to experience the same functions offered in CCleaner, but without leaving any evidence of use on the computer. It is the pocket version of CCleaner, an excellent cleaning utility tool with which you can erase unused files to gain back valuable free disk space and make your Windows desktop run faster and smoother. Many applications have developed special versions for these devices, usually known as ‘portable.' One of them is CCleaner Portable. As USB sticks and other flash memory drives increase in storage capacity, so does their popularity as software repositories.

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