The VirusTotal.com Web site offers a free but invaluable security service. It will scan any Web download, e-mail attachment or other file you send it with 40-odd different antivirus scanners to let you know whether it's safe for your computer. The VirusTotal Uploader utility makes sending a file to the site a breeze by adding a new right-click option for any file.
Even the best antivirus product can still miss some malicious files, but the odds of a baddie sneaking by go way down when you get 40 different scans, as you do at VirusTotal.com. You might also see a few false positives, so getting just one or two generic-looking warnings probably doesn't mean you have anything to worry about. And a clean scan doesn't completely guarantee that a file is safe--but it's still a very good assurance.
To upload a file, you can visit VirusTotal.com, click the Browse button to select a file from your hard drive, and then click the Send file button. Or you can make it even easier with the also-free VirusTotal Uploader utility. After installing it, you can simply right-click any file under 20MB and choose "VirusTotal" from the Send To menu. The scan results will display in your browser as per usual.
The latest version 2 of the VirusTotal Uploader utility adds a new program window with some useful extra features. For starters, you'll see a list of all the programs currently running on your PC. To get a VirusTotal scan on any of them, select it and click the "Upload process executable" button.
Another handy option--and one that's exclusive to the uploader--will have VirusTotal fetch and scan an online file without your even having to download it first. Type in the URL, or right-click it and choose "Copy link location" to cut and paste it, and then click the "Get and upload" button. The file will skip through your computer's memory, but will never save to your hard drive. You'll get the usual list of results and can then decide whether you want the download.
Since the vast majority of malware infections start with a Web download or e-mail attachment, VirusTotal's excellent free service is a must-have for your security arsenal.