In the past, rootkits have been an essential component to a computer. Its main function and the primary reason why it was created was for advanced PC users to have administrator access to a certain computer without having to login the usual way. In short, a rootkit enables administrators to login without being noticed

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Scan and Remove Rootkits with RootkitBuster
Did you know that with a usual system, uninstalling a program will not totally remove all its components including some of the data stored in the registry? This is especially true with antivirus, security tools, PC boost, spyware removers, and the likes. If you want to completely uninstall a security-based application and replace it with another one, try AppRemover.

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Completely Uninstall Antivirus Software Down to the Registry
Internet Explorer 8 (IE8) freezing often or failing to load could be happening because of several probable causes. For the most part, fixing Internet Explorer 8 is easy to do, but it may require that you check and diagnose several different areas in order to pin point the exact cause of the slow load times or freezing

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Repair Internet Explorer 8 Freeze or Fail to Load
Many students these days buy their textbooks in electronic, PDF format. The main advantage of this, besides price, is that the PDF can be carried on iPhones and laptops, so we have less junk to carry throughout the day. Unfortunately, most of these e-books have restrictions on how many pages from the PDF, if any, can be printed, and forget copying any text from the PDF.

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Remove Printing Restrictions and Passwords from PDF Files
Very rarely do you see the default Windows 7 firewall display a prompt that it prevented an attack on your PC.

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10 Free Windows 7 Firewall Apps