Run this if you have Windows. It will keep you from a mess on your computer if it catches malware etc...
Microsoft Safety ScannerDo you think your PC has a virus?
The Microsoft Safety Scanner is a free downloadable security tool that provides on-demand scanning and helps remove viruses, spyware, and other malicious software. It works with your existing antivirus software.
The Microsoft Safety Scanner expires 10 days after being downloaded.
To rerun a scan with the latest anti-malware definitions, download and run the Microsoft Safety Scanner again.
The Microsoft Safety Scanner is not a replacement for using an antivirus software program that provides ongoing protection.
For real-time protection that helps to guard your home or small business PCs against viruses, spyware, and other malicious software, download Microsoft Security Essentials.