Kaspersky Small Office Security 2 for File Server

Scan of compound files by File Anti-Virus in Kaspersky Small Office Security 2 for File Server

Applies to Kaspersky Small Office Security 2 for File Server

A common method of concealing viruses is to embed them into compound files, for example archives. To detect viruses that are hidden this way a compound file should be unpacked, that can significantly lower the scan speed.

File Anti-Virus in Kaspersky Small Office Security 2 for File Server allows to flexibly configure scan settings of compound files. You can:

• modify the list of scanned compound files
• select unpacking mode of large compound files
• specify the maximum size of unpacked compound files 

Installer packages (files to install different applications) and files containing OLE objects (objects: pictures, texts, tables etc., which are created in one application by can be opened by another application) are executed when they are opened, which makes them more dangerous than archives. By disabling archive scans and enabling scans for these file types, you can protect your computer against execution of malicious code and, at the same time, increase the scan speed.

Creating the list of scanned compound files 

In order to modify the list of scanned compound files:

1. Open the main application window.
2. In the left part of the window go to the Protection Center tab.
3. In the top right part of the window click the Settings link.

    

4. In the left part of the Settings window select the File Anti-Virus component.
5. In the right part of the window in the Security level section click the Settings button.

   

6. In the File Anti-Virus window go to the Performance tab.
7. In the Scan of compound files section check the boxes for the types of compound files to be scanned by File Anti-Virus:
   • Scan archives 
   • Scan installation packages 
   • Scan embedded OLE objects

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Scanning compound files in background mode

When accessing a compound file, the application needs to extract the file from an archive to scan it. Extracting large-sized files may considerably slow-down the scan process, whereas files under scan become available after the scan is complete.

To avoid the situation, the application can scan large-sized objects in the background mode. During background scan (which is imperceptible for the user) access to files under scan is not restricted. If a virus is detected during the file scan, the application will notify you of virus detection.

In order to enable Kaspersky Small Office Security 2 for File Server to unpack large-sized files in the background, perform the following actions:

1. In the File Anti-Virus window on the Performance tab in the Scan of compound files section, click the Additional button.
2. In the Compound files window, check the Extract compound files in the background box.
3. Specify the Minimum file size in the field. 

 

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Restricting size of a compound object

In order to increase the scan speed, you can disable unpacking files sized larger than the specified value. To reduce the delay when accessing compound files, you may disable unpacking the files of a size, which is larger than the specified value.

In order to not unpack large-sized compound files, perform the following actions:

1. In the Compound files window, check the Do not unpack large compound files box.

   Kaspersky Small Office Security 2 scans large-sized files extracted from archives even if the Do not unpack large compound files box is checked. 

2. Specify the file size in the Maximum file size field.
3. Click OK.

   

4. Close the File Anti-Virus window by clicking the OK button in the bottom right corner of the window.
5. In the Settings window click the OK button.
6. Close the main application window.

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Useful references

How to open the main application window of Kaspersky Small Office Security 2 for File Server?
What is File Anti-Virus in Kaspersky Small Office Security 2 for File Server?
How to enable heuristic analysis in File Anti-Virus in Kaspersky Small Office Security 2 for File Server?
How to change security level of File Anti-Virus in Kaspersky Small Office Security 2 for File Server?
File Anti-Virus operation algorithm in Kaspersky Small Office Security 2 for File Server

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