CCleaner

CCleaner is the best cache/cookie clearing app out there.  You will be amazed how much faster your system is after running it.

CCleaner clears out temp files, cache files, cookies, as well as emptying the recycle bin.  Partner running this with Auslogics Disk Defrag for the maximum PC speedup in the shortest time.

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Process Explorer

Process explorer is an updated and far more powerful version of the Task Manager built into the windows operating system.  It allows the ability to kill multiple processes at once, shows a tree based process view, and can show detailed information about each process.  Process explorer is created by the sysinternals branch of microsoft and is a free product.

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