This dialog box is displayed if a filename is invalid or if WinZip® was unable to open the specified archive or read the archive folder. It is possible that the file is not an archive or does not exist. Alternately, it is possible that the archive has been corrupted. Other reasons for this error include insufficient memory and disk errors while reading the archive.
If you are working with a Zip file, you can try repairing the file as described in the section Fixing Zip Files.