What is a virus?

Virus is a malicious piece of software or code, which is written intentionally for the destruction of data or malfunctioning on computers. It doesn't have its own entity. It has two prominent features i.e. execution and replication.

What is a worm?

A computer WORM is a self-contained program or set of programs that is able to spread itself to other computer systems (usually via network connections). Worms unlike viruses don't patch themselves to the executables files. They work independently.

What is a Trojan Horse?

A Trojan Horse is a fake file that pretends to do something desirable but on execution it infects the system. It does malicious activity without the user's knowledge.

What is a Backdoor?

Backdoor is an independent program. It has two components i.e. Server and Remote. Server component is installed on the victim system and remote component is the tool to control the victim system remotely. This is basically used for the hacking.

What is Adware and Joke (Prank) files?


A program that secretly gather personal information through the Internet and relay it back to another computer, generally for advertising purpose. This is often accomplished by tracking information related to Internet browser usage or habits.

Joke (Prank):

A program that change or interrupt the normal behavior of your computer, creating a general distraction or nuisance.

Why Trojan, Worm and Backdoor files are not repaired?

As they have their own independent programs which replicates it infection from computer to computer unlike viruses that replicates from file to file. They don't patch to executables or any other files. Hence deletion of their files cure the system.

What is denial of service (DOS) attack?

A Denial of Service (DOS) attack is a method that hackers use to prevent or deny legitimate users access to a computer. DOS attacks are executed using DOS tools like TFN, TFN2K etc. These tools send many request packets to a targeted Internet server (usually Web, FTP, or Mail server), that floods the server's resources, making the system unusable.

What are rootkits?

Rootkit refers to maliciously modified set of administrative tools that grants administrator access to the intruder thus giving them full control of the system. Rootkits typically hides files, processes, network connections, blocks of memory, or registry entries from other programs used by system administrators to detect specially privileged accesses to computer system resources.

What are packers? Why are certain packers dangerous?

Packers are tools that pack multiple files together. It can also be used to compress a single file. This is done to reduce the file size. Packers have an inbuilt functionality of packing and unpacking and hence do not need a third party application for the same. Packers are now being used to spread malware by packing a malicious file along with a set of non-malicious files. There are three types of packers:

 Black Listed Packers: All highly suspicious packers belong to this category.

 Gray Listed Packers: These packers may, or may not be suspicious.

White Listed Packers: All safe packers belong to this category.

What is a false positive?

If virus is detected in a clean file it is referred to as false positive.

Can I use more than one anti-virus software on my computer?

Running more than one anti-virus on your computer is not recommended unless specified specifically by the vendors. Anti-Virus product has some modules like real time scanning of files and real time scanning of mails, which seemingly integrates with OS to provide such services. Such integration can cause problems if there are multiple such services being installed and doing the same task. This way technical issue may arise as such modules are not designed with keeping such things in mind. Technical issues may cause your system to freeze repeatedly which may lead to data loss or unstable system etc.

Why do you recommend to not use full share access features on computer?

Allotting full share access rights to drives and folders could be dangerous for data, system & entire network. Virus threats increase if a full sharing rights is assigned to folders or drives. Currently new viruses tend to replicate immediately if they find share level access on computers. Avoid using full sharing on your computer but in case if data has to be shared in network then sharing rights should be assigned READ ONLY or PASSWORD PROTECTED.

Steps to share/unshare your folder & drive:

 Double-click My Computer on the Windows's desktop.

 Right-click on drive or folder to be shared, click on sharing tab.

 Look at sharing status:

 If not shared is checked Press OK.

 If shared as is checked, we recommend that you disable this option by checking Not Shared.

 If you have to share this volume, then under Access Type check either Read-Only or Depends on Password.

 You can create separate passwords for read-only and full access. Give the Full Access Password only to those who need it.

 For all other shared files and folders, make sure Access Type is set appropriately

How to disable System Restore feature on WINME/XP?

 Disable System Restore under Windows Me:

 Point to Start, Settings, and Control Panel. Double-click 'System', then click on the 'Performance' tab. Click 'File System' then click the 'Troubleshooting' tab. Select 'Disable System Restore' and click 'Apply'. Restart your system.

 Disable System Restore under Windows XP:

 Point to StartControl PanelPerformance and Maintenance. Double-click "System", then select the System Restore tab. Select the 'Turn off System Restore" on all drives box. Click Apply. Click Yes. Restart your system.

What is Quick Heal? What platforms does it run on?

 Quick Heal is anti-virus software that provides reliable and constant virus protection in a single, fully integrated product to the computers. It can be installed on Windows NT/2000/XP/2003; Windows 95/98/Me; DOS/Windows 3.1x and NetWare computers. It provides both on-access and on-demand scanning.


Does Quick Heal detect all in the wild viruses?

Yes, Quick Heal does detect and repair all in the wild viruses.

Where can I find technical details about viruses on Quick Heal website?

Technical details of latest viruses can be obtained from