Tools

Online Virus Scanner

Virustotal
Analyzes suspicious files and facilitates multiple antivirus quick detection of viruses, worms, Trojan horses

VirSCAN
VirSCAN.org - a multi-slide free online virus scanner checks files for viruses 37 different anti-virus

Metascan Online
Online Anti-Virus from OPSWAT Metascan Online allows you to quickly check the files to 40MB for viruses and malicious code

Jotti
Free Online Scanner Jotti allows you to check suspicious files for viruses using multiple anti-virus

OffLine Database Update

Microsoft Security Essentials
Microsoft Security Essentials x86
Microsoft Security Essentials x64

Avira
Avira Antivir Virus Definition File Update

Dr.Web
Dr.Web Virus Definitions Update

BitDefender
BitDefender 2012 Virus Definitions Update x86
BitDefender 2012 Virus Definitions Update x64

Symantec
Symantec Virus Definitions Update

F-Secure
F-Secure

Sophos Anti-Virus
Sophos Anti-Virus

Kaspersky Lab
Database Update

avast5!
avast5! Virus Definitions Update

AVG
AVG Software Updates
AVG Free - Update

TrendMicro
TrendMicro

Panda
Pandasecurity

Malwarebytes' Anti-Malware
MBAM-Rules

VirusBuster
Virus database updates

eScan antivirus
Weekly Offline Updates for eScan

Comodo Anti-Malware Database
download complete database

Zillya!
Anti-virus databases

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