If you received this message while extracting or testing files in a Zip file, one or more of the files is encrypted 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.
Assuming that the correct password is supplied, WinZip is able to decrypt files that have been encrypted using the following encryption methods, subject to the version requirements noted:
Please reach out to support if you have any additional questions about the encryption methods supported by WinZip.