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Unable to Extract .zip Files

The following error message may be displayed on your Windows Vista computer, when you try to use the WinZip utility to extract a compressed file with the .zip file name extension:

This file was compressed using an unknown compression method. Please visit for more information. The compression method used for this file is 98. error: no files were found - nothing to do

Cause of the Error

This problem occurs in the following conditions:

  • The zip file you are trying to extract was created using WinZip 10.
  • You have an earlier version of WinZip on your computer.

Now, the compression method used by WinZip 10 is incompatible with some Windows versions and some earlier WinZip versions. This is the reason why the error message given above is displayed when you try to open a WinZip 10 file with an earlier WinZip version on a Windows Vista computer.

Workaround Method

To prevent and work around this problem, do the following:

  1. Open WinZip 10.
  2. On the File menu, select the New Archive command.
  3. In the File name box, type the name for the compressed file, and the select the OK button.
  4. In the Add dialog box, browse and select the files that you need to add to the compressed file.
  5. In the Compression box, select the compression technique as Maximum (portable), and then select Add.

When you create an archive using the Maximum (portable) compression technique, the file can be opened using earlier WinZip versions.

If you need more information about the error message, you may open the following WinZip Web site:

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