An online virus scanner should never be considered a substitute for an installed antivirus scanner. But if you suspect your installed antivirus is missing a threat or you simply want a second opinion, an online scanner can be a valuable adjunct to security. Each of the following online scanners are considered best-of-breed and can offer important adjunct protection.

1) Trend Micro Housecall

Trend Micro's Housecall is the only one of our Top Online Scanners to offer cleaning or deleting of infected files. Housecall can scan the entire system, or selected drives and folders. Trend's new version of Housecall is slower and more cumbersome to navigate than previous versions. Updates and detection are not quite as reliable as the Kaspersky options below. Select Housecall only if cleaning or deletion is desired.

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2) Kaspersky Online Scanner

The fast and extremely efficient Kaspersky Online Scanner can be configured to scan individual files, folders, and drives - or target all email related files found on local and mapped drives. Kaspersky updates much more frequently than most other vendors and their heuristics (unknown virus detection) are among the best. This makes Kaspersy online scanner one of the most reliable available. Detection only.

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3) Kaspersky File Scanner

The online Kaspersky File Scanner checks single files less than 1Mb in size. Multiple files can be zipped as one and scanned, provided the resulting archive is 1Mb or less. With unsurpassed Trojan detection, Kaspersky Online Virus Scanner is ideal for checking email and IM attachments. Detection only.

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4) Virustotal

You can submit single files only to Virustotal, via their online scanner or by email. File size must not exceed 5Mb. The file is scanned by several different scan engines and results reported for each. Detection only.

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5) Jotti Online Malware Scan

Like Virustotal, Jotti returns scan results for several different scanners. The scan engines used by Jottie differ from those used by Virustotal and thus it's often worthwhile to use both. Detection only.

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