The Conficker virus differs from other viruses online because it is one of the few malicious worms that have already learned how to protect themselves from deletion. One of the first steps that all of the different variants of the virus take is to disable all anti-virus software and updates that you may have on your operating system. This ensures that the hole it entered through stays open so that it can continue to host and download files on your computer without any interference. Additionally, once you have the Conficker virus, it pays close attention to your browsing habits, disabling your entry to any websites such as Microsoft or anti-virus websites that could help you rid your system of it.

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How Do I Remove Conficker After It Disables My Antivirus?