Zip Component, Email Component, Encryption Component ActiveX Control for Zip Compression .NET Components for ASP.NET
ActiveX and .NET Components for Zip Compression, Encryption, Email, XML, S/MIME, HTML Email, Character Encoding, Digital Certificates, FTP, and more ASP Email ActiveX Component

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November 20, 2007

Unsupported Compression Method

The Chilkat Zip component can produce WinZip-compatible AES encrypted .zip archives. WinZip added it’s AES encryption capability with version 9.0 of its product. Therefore, if you try to use WinZip 8.0 and under to unzip an AES encrypted Zip, you will get the error: Unsupported Compression Method. This is because the AES Encryption compression method is 99. It will not be recognized by earlier versions of WinZip.

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