Version 4.2 offers the following new capabilities which were not available in v4.1:
A listing of a zip file's contents can now be obtained in the form of a collection object for increased performance and easy access from within Active Server Page scripts
Convert any type of zip file (regular, spanned, multi-part, self-extracting or spanned self-extracting) into any other type of zip file
Update one zip file from another one's contents or merge two zip files together
Filter out files during a zip file update, merge or conversion based on any file attributes or parameters
The library can now delete files after they have been successfully zipped. The library automatically verifies the destination zip file's integrity before deleting the zipped files. An event is triggered to inform the application whenever a file is deleted in this way
Files in a zip file can be renamed or have parameters (comment, time stamps, file attributes) changed in a single operation - no more need to unzipping and re-zip
Unused events can be prevented from being triggered for increased performance
File-by-file and global status report events also triggered while converting or filtering a zip file
You can now specify the amount of free space to leave on the first disk of a spanned zip file disk set
The library can now reject disks that do not have a specified amount of free space on them when creating a spanned zip file
Multiple external programs or executables can now be run by a self-extracting zip file
Self-extracting zip files can now extract each file to a specific location, including different target drives. Also, "folder macros" can now be used to specify common folders to extract to such as the System or Program Files folder
Self-extracting zip files can now copy one or more files from one location to another
Self-extracting zip files can now register DLLs (or other libraries) on the system
Self-extracting zip files can now add or change key values in the registry
