Article ID: 841120 - View products that this article applies to.
After you download a .ZIP file from a Microsoft Windows SharePoint Services document library, and then you try to open the .ZIP file, you may receive the following error message:
Cannot open file: it does not appear to be a valid archive. If you downloaded this file, try downloading the file again.
This problem may occur if HTTP compression is turned on in the Web Sites properties of Microsoft Internet Information Services (IIS) on the SharePoint virtual server. When you download a .ZIP file, IIS encodes the file as GZIP. However, the browser client passes the file directly to the unZIP program, without GZIP decoding the file.
To determine if HTTP compression is turned on, follow these steps:
To work around this problem, change the MIME type for the .ZIP file from application/x-zip-compressed to application/octet-stream. To change the MIME type, follow these steps:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Article ID: 841120 - Last Review: May 15, 2007 - Revision: 3.2