Cleaning compressed files

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Cleaning compressed files

File compression involves shrinking the size of a file or files using a data compression format. One of the most popular is the Zip format. Compressed files are useful for transferring information over networks because of the smaller file size.

For example, let's say there are five files, A.doc, B.doc, C.doc, D.doc, and E.doc: C.doc is infected with a macro virus, and they are all packed into a single compressed file called docs.zip: [docs.zip(A.doc, B.doc, C.doc, D.doc, E.doc)]. You can set PC-cillin to detect the virus in C.doc, issue an alert, and write the event to the Virus log. Because C.doc is in the first layer, PC-cillin will automatically execute the action you have specified when PC-cillin detects a virus up to the second layer. If you have selected the Clean viruses in compressed files check box. PC-cillin is able to carry out this action only if the infected file is contained in the second layer or less of the compressed file.

However, if C.doc was located in a deeper layer of compression, for example, {docs1.zip[docs.zip(A.doc, B.doc, C.doc, D.doc, E.doc)]}. Although PC-cillin could detect it (if you have set your scan compression layers to a number greater than three) it is unable to perform any scan action. Therefore, if you want to clean C.doc, use WinZip, or another compression program to decompress the compressed file. When the individual files have been decompressed, right-click C.doc and click PC-cillin. PC-cillin will perform the scan action you have set for Manual Scans.

To clean a compressed file:

  1. On the PC-cillin window, click Settings. The Settings window appears.

  2. On the Settings menu, click the Virus Scan link. The menu expands. Do one of the following:

  • To set Manual Scan virus scan actions, click the Manual Scan link.

  • To set Real-time Scan virus scan actions, click the Real-time Scan link.

Depending on the link you clicked, the Manual Scan or Real-time Scan screen appears.

  1. On the Manual Scan or Real-time Scan screen, under Scan action make sure Clean is selected from the Action when virus found list and select the Clean viruses in compressed files check box.

  2. Click Apply.

See also:

About virus scan actions

Setting virus scan actions

Setting virus scan actions if unable to clean file

Backing up files before cleaning