I Prefer to eject tapes from command prompt than Command View .
General Syntax :
omnimm -eject LibraryName {Slot | FromSlot-ToSlot} [-location Location]
Command Usage :
omnimm -eject "MYLIB" 4
omnimm eject "MYLIB" 4 5 6 7 22 (to eject slot no 4 ,5,6,7 and 22 Tapes).
Other Usefull Commands:
uma -ioctl to scan and know mail slot status.
TIP : Make sure tape library in idle position while ejecting.