You get an error saying 'Unable to lock volume for exclusive access'
A.K.A. 'DeviceIoControl(FSCTL_LOCK_VOLUME) Failed!'
Answer:
If the 'Reason' given is 'Invalid function' (or words to that effect)
You need to update your IDE drivers. Your current ones are old and don't support this IMPORTANT feature.
If the 'Reason' given is 'Access is denied' (or words to that effect)
Another program is currently using the drive. You need to find out what it is and shut it down!
The only way I know of finding out what else has a 'handle' open to the drive is by using
Process Explorer from
www.sysinternals.com
Load it up and click 'Find' -> 'Find Handle...'
The type 'cdrom' and click 'search'
See if it comes up with any results
If it doesnt, try searching for the drive letter of that drive - i.e. 'F:'
If it finds something, click on it in the search window. The main window should then highlight the process / 'File' entry that contains the handle to the drive. You can right click -> close the handle if you like, or just close the entire application, it's up to you.
You may also get error 'Unknown (34)' sometimes