Each CMS user is allocated a certain number of Cylinders of Z Space when a CMS account is applied for.
The Z Space is temporary space used by applications such as focus for storing temporary data and reports.
You can view the contents of the Z Space by typing
FLIST * * Z
If there are no files on your Z Disk, you will receive the following error message:
DMSCYF002E File not found
It is important that you
copy any report files you wish to save from your Z Disk to
your A Disk before you log off, otherwise the files on the Z disk will
be erased and you will have to re-run the reports.