You have been infected with the Navidad virus, you can run programs from the command prompt and the first thing you should do is update your anti-virus program. If you don't have an anti-virus program now is the time to buy one.

To update your virus program click on start, run, and type www.pcrescue.com.au, your web browser will open. From there you can navigate to your anti-virus' vendors website where you will find instructions to update your virus checker as well as tools to remove the virus.