Trojan. I would suggest running Malwarebytes to see if it will kill this trojan
Somehow this fake Anti-Virus program has found it's way into your system.
The article below is by Microsoft probably aimed at Win 7, 8, 8.1 users but will hopefully apply to XP.
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Cloud AV 2012 is a variant of Win32/FakeScanti - a family of trojans that claim to scan for malware and display fake warnings of "malicious programs and viruses". It then informs the user that they need to pay money to register the software in order to remove these non-existent threats. The malware may also attempt to terminate processes and block access to websites.
What to do now
To detect and remove this threat and other malicious software that may be installed on your computer, run a full-system scan with an appropriate, up-to-date, security solution. The following Microsoftproducts detect and remove this threat:
Microsoft Security Essentials
Microsoft Safety Scanner
Windows Defender
Microsoft Windows Malicious Software Removal Tool
For more information on antivirus software, see
http://www.microsoft.com/windows/antivirus-partners/.
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Hope you can kill the thing,
Cheers,
Aunty Jack.