Decompression of zip file fails with error "unsupported compression method 99" on Red Hat Enterprise Linux 5

Solution Verified - Updated -


  • Red Hat Enterprise Linux 5


  • When trying to extract winzip (3rd party application ) password protected  file below error appears.
unsupported compression method 99  
  • How to extract password protected zip files (Compressed using WinZip Application) on Red Hat Enterprise Linux 5,?


  • Compression method 99 error indicates the AES (Adavance Encryption Standard) encryption. Unfortunately, This encryption standard is currently not supported by unzip binary.

  • However, 7zip package can be used to extract such files. 7zip is available in EPEL project to extract winzip password protected file.

  • Instruction on how to use EPEL repository can be found at : How to use Extra Packages for Enterprise Linux (EPEL) ?

Note: Red Hat Global Support Services will be unable to support or debug problems with packages not shipped in standard RHEL channels. Installing packages from EPEL is done at the user's own risk.

Root Cause

  • Winzip program uses AES encryption method to make zip file password protected which is not supported by unzip binary.
  • Component
  • zip

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