Corrupt files when using Vista Extract All with large encrypted ZI

[Guest]

When unpacking some ZIP files using Extract All in Vista Home Premium 32bit,
I have found that some of the extracted files are corrupt.

I can drag the individual file out of the ZIP, so the problem is not that
ZIP is corrupt. A Vista machine with WinZip installed will unpack the files
OK.

Looking at a corrupted file, the first 2MB exactly are OK, but the remainder
is filled with zero bytes.

From trying different combinations, it seems that for the corruption to
occur,
- the zip must be password protected
- the original file must be large ( much larger than 2MB)
- the original file must be inside a folder in the zip

The simplest example I have created consists of a single folder containing a
single 14MB text file. The folder is zipped with WinZip on another machine,
using ZIP 2.0 compatible encryption. This file has has been tested on a
couple of Vista machines and the corruption occurred on both.

 

[Guest]

Yeah I've had the corrupted zips problem, and I'm using home premium. It
doesn't always happen on extracting either, it also happens when creating big
zip files. I use 7zip now to extract the zips and I only create 7z archives
now. Much better than Vista's zip program.

 

[Guest]

Thanks for the confirmation.

I don't really want to tell people to install software when I send them a
ZIP, especially considering the number of posts from people having problems
with the ZIP file association.