Un-mount trough batch

Hello.
I got a copy of my game on my computer.
The thing is, i like to keep it .iso, for space saving.
Now i created myself a batch file, where it mounts the file in VirtualCloneDrive, and launches the game on key down.

The thing is now, when i exit my game, the window is still there, and then i want it to unmount on key down. i know how to eject the disc, but have no clue on the unmount, sins I haven't much experience with batch at all. I just read, and created the working batch. Would anyone know of a command that makes it unmount?

I would be so glad if i got some serious response on this one

 

OK, I tried this now.
All i get is that "VCDMount" ain't a internal, external or a runnable program.
I even changed the drive to H: first, with is the VCD disc. Could you give some more explaining info please?

 

OK, i got it all working now, thank you!

In case someone want to see the bat i created now, ill post it as code below here.

Code:

@echo off
tra.iso
cls

@echo Tomb Raider Anniversary Disc is ready!
@echo Push a button to start game...
@echo off
Pause

H:
tra.exe
cls

@echo Push a button to un-mount disc and quit...
@echo off
pause

cls
c:
cd programfiler
cd "Elaborate Bytes"
cd VirtualCloneDrive
VCDMount /u
exit