When it comes to unlocking files I always did that with another freeware tool named unlocker. You can try to unlock the files with this tool, it has always worked for me. http://ccollomb.free.fr/unlocker/#description
If I were you for the estimation of size being written on a CD/DVD I would use a third-party CD/DVD burnerlike imgburn. http://filehippo.com/download_imgburn/ It's way better than what windows is offering and you can also customize anything with one or two buttons.
I have been having trouble clearing files from my CD writing folder after the files could not be copied to CD. The computer keeps saying the files are in use by another program and won't copy or delete them.
Specifically these are photoshop files and photoshop is not running.Although this has happened with other file types as well.
In the past I've been able to deal with this situation by restarting windows and then deleting..not working this time though ..any thoughts?
Also..while I'm here...is there a way to anticipate the amount of files that will fit on a dvd or cd before attempting to copy them...other than the obvious and often laborious task of adding the sizes of each file or folder?
Thanks.

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