Created attachment 94755 [details] zip file ark failes on Current owncloud development version (8.2) creates zip files for multiple file downloads on the fly, setting zip standard general purpose bit 3 and thus ommitting crc and compressed size in the local file headers. Additionally, these zip files are always in zip64 format. To my knownledge, these files are standards-compliant (I'm the developer of the php library that creates the files in owncloud, and thus have thorough expertise on the zip standard, but I'll be happy to be corrected if wrong anyways). Ark 2.19 on Debian 8.2 fails to open such a zip file and gives an error message: "Loading the archive test.zip failed with the following error: The archive reading failed with the following error:" (so the actual error is ommited in the message). This might indicate libarchive being responsible for the error, but I do not have time to delve more into this. Anyways, Ark 2.17 on my Knoppix 7 happily opens the file and displays/extracts its contents correctly (another indication that the zip files are indeed standards-compliant). I attached a file exposing the described behaviour. If it turns out you can pinpoint the problem to the zip files not being standards compliant, you can use the existing bug report on the owncloud zip component to tell me more so I can fix the issue: https://github.com/McNetic/PHPZipStreamer/issues/25.
This is probably due to Debian/Ubuntu patching Ark in order to use libarchive for zip archives. The libarchive plugin is not supposed to be used for zip archives. In fact, the test archive is opened as expected using the default zip plugin. Debian/Ubuntu apply that patch in order to fix the bad unicode support in the default zip plugin (which is info-zip). The problem is that libarchive has its own issues with the zip format. That's why we are trying to make p7zip the default zip plugin, for the next Ark release. This should definitely clean up this mess, hopefully.