There are MANY viruses and malware code which the most sophisticated anti-virus products simply can't protect you from. One of which is a variant of the Phoenix virus which includes several different forms, not all are the original Phoenix virus but all contain the term "Phoenix" within its definition.
The most violent form begins by attacking your browser and looks to log your keystrokes to obtain user names, passwords, etc. If more than one browser is installed, such as Explorer, Firefox, Opera, etc., it will spread to each and also corrupt system files.
As this virus propagates, it'll attempt to attack your computer every few seconds while a browser is functioning. Products such as Nortons and McAfee will "block" the virus at each attempt but as this attack continues over the course of several days, your system will not respond and result in a black screen at startup. At this point most will result in reinstalling the operating system which is time consuming along with the loss of all files and applications.
This particular virus is usually contracted by visiting "unsavory" websites, downloading commercial software which requires you to modify the "Hosts File" of your system (advanced) and by downloading products compressed using .RAR compression.
The solution? Every week or so, create a "System Restore Point". Information on this can be found on Microsoft's website. The beauty of System Restore is it brings all system and vital files back to their original state while keeping all your files and applications intact while cleaning your computer of all unwanted files not present at the restore point set.
So basically, System Restore is your best defense against super viruses without the loss of saved files.
You'll require your original Windows Install Disk to initiate the restore in the event of a super virus attack so don't lose them. If not receiving disks with your system, make certain to follow manufacturers instructions on the correct method to create a set from the installed system.
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