[Macworld]

Post your comments for Unzip almost any archive file here

[macmanmk]

Or you can use the free Stuffit Expander...useful for opening password protected archives.

[peerst]

The reason I encountered most often when this happens to me: the ZIP file is being produced by 7-zip but not stored with a *.7z extension but zip. This happens more often recently since some companies replace their Winzip licenses with free 7-Zip.

The archive container is then a normal ZIP but the compressed files are compressed with 7z or another method not supported by the Mac OSX built-in tool. Then you get the behaviour that you get a *.cpgz file instead of your content.

You need a unarchiver that supports 7z or just the 7z command-line tool.

But non standard ZIP files shouldn't be distributed with the *.zip extension anyway to avoid the false try to double click expand.

[ravencub]

The Unarchiver from the Mac App Store doesn't seem to work with zipped installer packages. The packages seem to unzip correctly, but give "installation failed" errors when executed. The developer instructed me to download the older version directly from his web site, which corrects the issue. The first problem I've seen with sandboxed apps.

[ecdltf]

cpgz (gzipped cpio archive) is a common format; cpio is for example the default archive format of OSX's ditto tool. It can also be extracted seamlessly with OSX's ditto tool or even by double-clicking it in the finder (assuming Apple's Archive Utility.app is still assigned as default application for this file type).
No need for third party tools

Btw, you can create a cpgz on every Mac with 'ditto -cz'.

[xfadel]

I prepare software images for a university. In the fall of 2010, we encountered .zip files that The Unarchiver (and Apple's built-in unarchiver) could not handle that StuffIt Expander could open. We've had no complaints with Expander.

[redgeminipa]

I ended up using The Unarchiver to expand one of the Zeitgeist movies so the .iso could be burned to DVD. I discovered it on the Mac App Store, which popped up when I was asked if I wanted to find an app in the store to do the task. It worked like a charm for a free app (donations gladly accepted).

[bettercitizens]

Thanks for the terminal tip. That will come in handy...

[Back2Future]

ravencub, on 17 April 2012 - 05:34 AM, said:

The Unarchiver from the Mac App Store doesn't seem to work with zipped installer packages. The packages seem to unzip correctly, but give "installation failed" errors when executed. The developer instructed me to download the older version directly from his web site, which corrects the issue. The first problem I've seen with sandboxed apps.

I've sèent a couple of hours troubleshooting the "installation failure" error... and after that session I've discovered the "unarchiver" bug! :-(((

[dougcarden]

I had the same problem. File Juicer worked for me.

[dougcarden]

I had the same problem. File Juicer worked for me.

[Petew]

dougcarden, on 17 April 2012 - 02:11 PM, said:

I had the same problem. File Juicer worked for me.

Kudos to you sir! Great application.

[Biallystock]

Stuffit also does the trick. Lots of people love to bag Stuffit but is really a very good unarchiving tool. Just don't create an stuffit files.

[LRhodes]

Biallystock, on 21 April 2012 - 10:52 PM, said:

... Just don't create an stuffit files.

But they're the only convenient compressed archives that preserve creation dates -- Apple's zip tool and disk image from folder don't. Some of use would rather not lose that information.