Raymond.CC Blog

Kaspersky has a free utility designed to provide on-demand scan and remove all types of virus infections from your computer. The official name for the tool is Kaspersky Virus Removal Tool but some people call it AVPTool. Do take note that Kaspersky Virus Removal Tool is NOT meant to replace your real-time protection of your computer. Whenever a currently installed antivirus software such as Norton, NOD32, Bitdefender, AVG, Avira and etc fails to detect and remove virus on a computer, I’d first use Kaspersky Virus Removal Tool to perform a full scan on system memory, startup objects, disk boot sectors, and the hard drives.

No matter how good and useful AVPTool is, there’s one big inconvenience with this utility that is it doesn’t have an update feature. If you’re using AVPTool that is downloaded yesterday, you’ll get a warning from the utility telling you that “The threat signatures are obsolete. You are advised to update the program.” And when you’re using a much older version of AVPTool, the utility will tell you “Kaspersky Virus Removal Tool is out of date. You are advised to update the program” Clicking the Last version of program link from the warning popup balloon will open your default browser to start downloading the latest version which is 27MB in size and growing each time because of the updated signatures to detect latest viruses.

Since I use AVPTool very frequently, I had to find a way to manually update the virus definition database without re-downloading the 27MB setup. I am glad that I manage to find a way to update AVPTool and also sharing it with you.


As far as I know, Kaspersky virus definitions are stored in “bases” folder. The updated Kaspersky virus definition database can be easily downloaded from their server and most of the files there are with .avc extension. When I checked the AVPTool bases folder, most of the files are with .avz extension and it has a huge megabase.avc file that is 21.8MB in size. I found out that the megabase.avc file stored in the AVPTool bases folder is actually multiple .avc files merged into one giant file.

Although the file extensions between AVPTool bases and Kaspersky server are different, the secret is AVPTool can also use definition files in .avc extension. So all you need to do is to download all the files from Kaspersky server to the AVPTool bases folder.

There are 700+ files in Kaspersky server and manually maintaining the AVPTool definition updates is not going to be easy. So here is a tool called NOD32 Update Viewer (NOD32View) which is actually meant for checking NOD32 definition files updates but has been improved to support AVPTool, DR. Web, AVZ, Trojan Remover and A-Squared. I am going to show you how easily it is to maintain an updated AVPTool using NOD32View.

1. Download the latest version of NOD32 Update Viewer and install.

2. Download the latest version of Kaspersky Virus Removal Tool and install. By default it will try to install Kaspersky Virus Removal Tool to your desktop and create a new folder Kaspersky Lab Tool.

3. Once AVPTool finished installing, it will automatically run. Click the Settings area, uncheck “Enable Self-Defense” and click OK.

Close AVPTool and click NO when you see a prompt that says “The program will be unloaded and uninstalled. Do you want to uninstall?”

4. Launch NOD32View and click the Kaspersky icon.

5. Click the small folder icon to select the path for the Kaspersky Virus Removal tool bases folder. If you installed AVPTool to desktop, the path should be something the following:
In Windows XP: C:\Documents and Settings\USERNAME\Desktop\Kaspersky Lab Tool\is-XXXX\bases\
In Windows Vista: C:\Users\USERNAME\Desktop\Kaspersky Lab Tool\is-XXXX\bases\
The XXXX is a randomly generated character during installation.

6. Click Check button, wait for a few seconds and click the Update button when it is no longer grayed out. Go make yourself a cup of coffee because the first time would a while to finish downloading 40MB of files. However, the next time would be much faster as NOD32View will only download the updated changed files. Everytime NOD32View finished updating the AVPTool definition, the .avc files will be automatically copied to the base path where you specified in step 5.

Now you know how to manually update your Kaspersky Virus Removal Tool signatures without re-downloading the latest installer.

Note: To run Kaspersky Virus Removal Tool, the filename