Problems unzipping files downloaded from Firefox using Windows built-in extractor tool
Hi, I am running Firefox v26 on a Windows 7 (64-bit) PC. I work for a library that is able to reproduce digital audio books that we can download from the Library of Congress's National Library Service (NLS) for the Blind and Physically Handicapped. I use Firefox to download a lot of zipped audio books for my job. The file formats found in one book's zipped folder often include the following file types: .3gp (they're like a more compressed MP3 audio file), .mp3, .ncx, .opf, .pncx, .ppf, .smil, .md5, .dtd, .ent, and .ao.
If I use Windows' built-in extraction tool to unzip an audio book I have downloaded via Firefox the extraction process ends prematurely and acts as if it was successful, but in reality some files are were never extracted. For example, I downloaded a zipped audio book that contained 21 files and weighed in at 87.6MB. The built-in Windows extraction tool only unzipped 2 files weighing in at 30.3MB.
I have downloaded this same zipped audio book using Google's Chrome v31 and IE 11. Both downloads unzipped successfully using Windows' extractor. To make things even more bizarre, I *was* able to successfully unzip my audio book that I downloaded using Firefox using a 3rd party extraction tool called Extract Now. Because I tend to use this 3rd party program to extract my audio files I don't know at which version of Firefox this problem started. All I know if that this hasn't always been the case.
Please help.
Thanks, -Dan M.
Modified by dmalosh
All Replies (6)
If you still have downloaded ZIP archives from a couple of weeks ago in your history, you may be able to compare Firefox 25.0.1.
In another thread, the issue of an apparent download security change has come up. When viewing the ZIP archive in Windows Explorer, do you notice a new lock icon appearing on the file icon with downloads you make in Firefox 26 that was not on downloads made in Firefox 25? Assuming so, try this: select the file, Ctrl+c to copy and Ctrl+p to paste. Windows will create a copy that should not have the icon. Does that ZIP file extract successfully, or same issue?
Thanks for your reply.
Unfortunately, I don't have any zipped folders prior to today's date. I typically download via Firefox and extract using Extract Now. Once all are extracted I delete all the ZIP archives.
I don't see any difference in the ZIP file icon, at least not when comparing the icon with the icons of the copies I downloaded using IE11 or Chrome. All 3 look the same.
I took my Firefox download and did a copy and paste in the same location, I also pasted in a new location, both gave me the same result: a partially unzipped folder. Any other ideas?
Can you compare the downloads from the different browsers to see whether they are identical? One way is to use the command line program fc (see: Microsoft Technnet: Fc) although that's not always convenient with deeply buried folders. Another is to use the open source program WinMerge, available at http://winmerge.org/. (To compare two files in the same folder with WinMerge, click the first and Ctrl+click the second, right-click either, and choose WinMerge from the context menu.)
Thanks again, and thanks for pointing out these 2 methods for comparing files. I was previously unaware of them.
I tried the File Comparison command to compare the zipped file I downloaded from IE with the one I downloaded from Firefox. FC claims "no differences encountered."
I also tried WinMerge. It claims that the files are identical.
I really don't know what to think on this issue. I don't know if there could be some setting that simply needs to be changed within my browser or what.
After downloading from other machines running the latest version of Firefox, I found that ONLY my primary, desktop PC is having this problem. I have downloaded the same file on a Windows XP (32bit) PC, Windows Server 2008 (64bit) machine, and a laptop running Windows 7 (64bit). In every instance I was able to completely and successfully extract all the files using Windows built-in extractor. Because of the success I had on the laptop - running the same OS and version of Firefox - I am beginning to feel this problem is localized to my desktop PC. However, I received an email from a colleague who claims he has had a similar issue on a Windows 8 machine. I'm waiting for more information on his claim.
Maybe uninstalling and reinstalling Firefox is the answer. I don't know...
Thank you for testing.
Since the contents are identical, I am back to thinking there might be an issue with file attributes, such as security settings. This would be consistent with my getting a little padlock icon on most of my downloads in Firefox 26. However, I don't know how to extract and compare that information.
Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test to see if that helps with extracting files.