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The wizard is designed mainly for use with memory chips and other FAT memory devices.  The process including scanning the complete disk so could be slow if a large hard drive is analysed this way.

The important parametrs to set are the start sector and cluster size.  When possible these are automatiucally determined.

On scanning, the program will scan the complete disk - thus for a large hard disk it may be slow which is why this function is most approriate for FAT disks that tend to be memory chips or smaller.

On scanning three elements will be searched for

• Head count - the is a PK 0x03 0x04 header found at the start of each block of compressed data, and contains the file name.
• The dir header is the PK 0x01 0x02 header.  This is the directory entry for each file and gives the size and offset within the main ZIP file
• Central pointer.  This is at the end of the Zip file and is a PK 0x05 0x06 header.  It points to the start of the directory.

After scanning the program will attempt to recreate Zip files.  This is process where a starting PK 0x03 0x04 is read and each file within it is read.  By knowing the length of the file it is possible to determine the location of the the next header.  Having scanned every cluster it is possible to find a cluster with a header in the correct location.  The chance of a false positive is not very likely, but to trap these the CRC value is tested, and if it fails, another cluster is tested.