Hi rotcejbo,
Welcome to Microsoft answers forums!
This issue occurs in special .zip files. If the .zip file contains folder items that do not have the directory flag set in the external file attributes field, the computer treats the items as files that are 0 bytes. Therefore, the issue occurs.
In Windows Vista SP1 and in Windows Server 2008, the computer parses files first. The 0-byte files are created before the folders. This behavior makes the extraction fail because the folder structure cannot be created.
You would suggest you to download and install the hot fix available, see the link below
Error message when you extract items from a .zip file in Windows Vista or in Windows Server 2008: "Error 0x800004005: Unspecified error"
http://support.microsoft.com/kb/952249
Let us know if this helps you
Thanks and Regards:
Ajay K
Microsoft Answers Support Engineer
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