Unsupported Compression Method

If you received this message while extracting or testing files in a Zip file, one or more of the files is compressed using a method that is unknown to your version of WinZip.

When this message is encountered, it is always possible that the Zip file is damaged. If possible, obtain a fresh copy of the file (e.g., by re-downloading it) and try again.

The compression methods that are currently defined by the Zip 2.0 standard are numbered from 0 to 10. WinZip supports methods 0 through 9, which are all of the methods that are fully documented and available for public use. The only method not supported is method 10, which is known as "DCL Implode." DCL Implode is a proprietary compression method that is typically used only in custom software and not in general-purpose Zip utilities. You will need other software to extract files compressed with DCL Implode.

Note: An 'Unsupported Compression Method' error will also appear if:

• You try to open, with WinZip 9.0 or earlier or WinZip Command Line Support Add-On 1.1 or earlier, Zip files created with WinZip 10.0 or WinZip Command Line Support Add-On 2.0 using the PPMd compression method.
• You try to open, with WinZip 8.1 or earlier or WinZip Command Line Support Add-On 1.0 or earlier, Zip files created with WinZip 10.0 or WinZip Command Line Support Add-On 2.0 using the bzip2 compression method.
• You try to open Zip files created using the WAVPACK compression format with WinZip 10.0 or earlier or WinZip Command Line Add-on.

If you encounter a compression method other than those listed above and are sure that your Zip file is undamaged, please contact support@winzip.com.