Computer experts believe that we are less from one day away from seeing the full effects of the Conficker worm.

The latest form of the virus, which has infected an estimated 15 million users worldwide, contains an instruction to perform a particular action on April 1, although nobody is yet sure as to what, if anything, that action is.

There are also suggestions that, given the hype over the worm, we could be about to witness the internet’s biggest ever April Fool’s Day joke.

The Conficker virus, also known as Downadup or Kido, has gained notoriety in recent months due to the rate at which it has spread as well as the number of high-profile organisations that have fallen prey to it. To date, several government, military and health systems are known to have been affected by the worm including the British Houses of Parliament IT system.

The virus buries itself deep inside the Windows operating system where it can then be used to steal users’ passwords and personal information, including bank details. It sets up files and starts downloading information from a controlling server, creating a “botnet” of infected PCs.

Many security experts believe that from midnight on April 1, the Conficker program will start scanning thousands of websites for a new set of instructions telling it what to do next.

Microsoft, which has released several security updates and urged customers to update their antivirus software, has offered a $250,000 reward for information that leads to the capture and conviction of the authors of the virus.

If you feel that you have been infected by the worm, download the free Conficker removal tool.

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