http://www.pkware.com/
Dort gibt es eine Testversion zum Download (PKZip), und wenn Dir das Programm gefällt kannst Du es gleich online kaufen
Vielleicht kannst Du damit deine Zip files reparieren:
Auszug aus der hilfe-Datei:
Q: How do I test a file?
A: Testing a file allows you to validate or verify that a .ZIP or PKSFX archive is not damaged. If an archive contains errors, you will be prompted to attempt to fix the problems. Please note that sometimes an archive is damaged beyond repair and cannot be fixed.
To test a file, follow these steps:
· Open the archive you wish to test by selecting File | Open or by selecting the Open toolbar button. You will only be able to test .ZIP and .EXE files.
· Select Extract | Test Files or select the Test toolbar item.
· A status window will appear as the files are tested. Any messages will also be reported to the Log tab.