I first stumbled on this a few years ago, when I had my ancient Windows 98, with only a six gigabyte hard drive. As I didn’t have a CD burner, “backing up” often meant compressing files into ZIPs and transferring to my mother’s computer. Needless to say, sometimes the ZIP files got corrupted during the transfer. In fact, one wrong byte can corrupt an entire ZIP.
Then I found DiskInternals Zip Repair.
I had about 200 images in a corrupted ZIP. I only lost one. As well, it’s very easy to use, and doesn’t let you accidentally overwrite the ZIP file while recovering.
I also recommend taking a look at their other software — judging from the trial versions, they look pretty good.