Follett VERSION 6.00 - Manual (Page 232)

04/04 232 Inventory
Marking items Missing outside an inventory
Occasionally there will be items that are missing from the shelf but have a copy
status of Available and an inventory status of Marked. If you're not in the middle
of an inventory, you can still change the inventory status of these items to
Missing in Cataloging.
Changing an item's inventory status from Marked to Missing also changes the
copy status from Available to Missing. For information about changing an item's
inventory or copy status in Cataloging, see Chapter 24, Working with copies."
Note: You can only change the inventory status of items that have a copy status
of Available. To change the copy status of a Lost or At the Bindery item to
Available, you must check in the item in Circulation Desk.
Deleting Missing items
If you are satisfied that your inventory is correct, you can delete the Missing
copies from your database. Or, if you prefer, delete only those copies that have
been missing for, say, three years. For instructions on the Global Delete Missing
Copies process, see page 330.