Windows – How to open corrupted ZIP files

The ZIP format has always supported archiving files with zero compression ratio, even since pkzip/pkunzip in DOS times.

Nowadays, almost all compression programs support this; 7-Zip is one of them, it lets you specify the compression ratio both from the GUI and from the command line, and it's free.

There are a few points you could consider:

• Choice of Browser. Some time ago, Internet Explorer often caused this kind of problem.

• FTP. If possible, you can try to get download from an FTP server via FTP (File Transfer Protocol) rather than HTTP (Hypertext Transfer Protocol). From the name you can see that FTP is dedicated to transferring files.

• Command-line download utilities. Dedicated software is often better than a browser for such tasks.

  Windows: BITSAdmin is the first one I found, but surely there is more.

  Linux: wget, etc.

• Internet connection. First of all, see if your internet is not breaking off every 10 minutes – while it does not affect web surfing, it can become a problem for downloading via some browsers (then command-line utilities could be a temporary solution). Also check if your cable is not damaged.

• Antivirus. If your antivirus is checking the files you're downloading bit by bit, it could delay the process and cause problems. Not saying you should turn your antivirus off when downloading unknown files, but you can do some tests of this kind if everything else fails.

In general, without further info about the problem you experience, it is hard to advise something.