List of All File Extension Viruses

Protect your computer.

The common definition for a computer virus is a program that can copy itself in order to infect a computer. While the term "virus" is often used to refer to other types of malware (such as adware and spyware programs), a virus is only capable of being spread from one computer to another in some form of executable code when its host is taken to the target computer. For example, when a user sends a virus attachment via email, or if an infected file is on a disk or flash drive, then the virus can be spread.

Common File Extensions

The classic computer virus arrives as an executable file, ending in .exe, or a Visual Basic file, which ends in .vb*. If you happen to receive an email with this type of file attached, you should always exercise extreme caution before opening it.

Other File Extensions

There are also many less common file extensions that can be used by a virus to infect a computer. Some of these include:

ADE--Microsoft Access Project Extension
ADP--Microsoft Access Project
BAS--Visual Basic Class Module
BAT--Batch File
CHM--Compiled HTML Help File
CMD--Windows NT Command Script
COM--MS-DOS Application
CPL--Control Panel Extension
CRT--Security Certificate
DLL--Dynamic Link Library
DO*--Word Documents and Templates
HLP--Windows Help File
HTA--HTML Applications
INF--Setup Information File
INS, ISP--Internet Communication Settings
JS--JScript File
JSE--JScript Encoded Script File
LNK--Shortcut
MD*--Microsoft Access Applications and Databases
MSC--Microsoft Common Console Document
MSI, MSP--Windows Installer
MST--Visual Test Source File
OCX--ActiveX Objects
PCD--Photo CD Image
PIF--Shortcut to MS-DOS Program
POT, PPT--PowerPoint Files
REG--Registration Entries
SCR--Screen Saver
SCT--Windows Script Component
SHB--Document Shortcut File
SHS--Shell Scrap Object
SYS--System Config/Driver
URL--Internet Shortcut (Uniform Resource Locator)
WS*--Windows Scripts
XL*--Excel Files and Templates

Make File Extensions Visible

One of the primary ways to protect yourself from computer viruses is to know what files you're opening before you open them. In Windows Explorer, you can open your folder options and select the option to always display file extensions.

Attachment Precautions

The majority of computer viruses are transmitted through email or instant messaging. A good rule of thumb is to never open a file unless you know exactly what it is. If you get an email with an unexpected attachment, you should not open it until you verify that it's legitimate and safe.

The Final Word on Safety

Of course, your computer should always be running anti-virus software with the latest definitions installed. You should also have a firewall, and keep your operating system updated with any necessary service packs or security patches.

Resources

• FAQs: Computer Virus FAQ for New Users
• Microsoft: Computer Viruses--Description, Prevention, and Recovery