Cleaning compressed mail files

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Cleaning compressed mail 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 Internet mail scans.

To clean a compressed mail 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.

  3. Click the Internet Mail Scan link. The Internet Mail Scan screen appears.

  4. Under Scan action, make sure Clean is selected from the Action when virus found list, and then select the Clean viruses in compressed files check box.

  5. Click Apply.

See also:

About Internet mail scan

Enabling Internet mail scan

Setting Internet mail scan actions

Setting Internet mail scan actions if unable to clean file