Unable to open ZIP Disk?

A client has contacted me with a Zip 100 disk that has somehow been compressed. All jpeg files on it were compressed and is now reading Dblspace.000, and a read me text file that explains how to mount said disk. When a mounting attempt is made it caused the system to crash. Diskscan cannot access this file and neither can guest.exe through command prompt only on another machine. How might I retrieve this data for this customer?